eLinux.org - User contributions [en]

R-Pi Troubleshooting

2013-05-09T11:36:55Z

Meltwater: /* Red power LED is on, green LED does not flash, nothing on display */ - added more info about SD card contacts (from recent forum help)

[[Category:RaspberryPi]]

Back to the [[R-Pi Hub|Hub]].

This page lists the most common problems and suggests some solutions.

See [[RPi_Bugs]] for problems that are bugs.

==Power / Start-up==
A good power supply that will supply 5 volts and at least 1 amp (5V 1A) is vital. A 5 volt 2 amp power supply can help some wifi USB adapters run more stable. For more information see [[#Troubleshooting_power_problems]].

Note that the Pi has no BIOS, so nothing will be displayed on screen unless the Pi successfully boots!

===Normal LED status===
There are five LEDS near the USB connector.
{| border="1"
|+ LED statuses
! LED
! colour
! function
! normal status
|-
| ACT || green || card status || flashing during SD card activity
|-
| PWR || red || power || steady ON when Pi receives some power
|-
| FDX || orange || full duplex || on when Ethernet connection is full duplex
|-
| LNK || orange || link || on when Ethernet is connected
|-
| 100 || orange || 100 Mbps || on when connection is 100 Mbps off when 10 Mbps
|}

See the next sections for how to interpret other statuses.

===Red power LED does not light, nothing on display===
The power is not properly connected.

===Red power LED is blinking===
The red power LED should never blink, because it is hard-wired to the 3.3V power supply rail. If it is blinking, as one user has reported<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=7528</ref> it means the 5V power supply is dropping out. Use a different power supply.

===Red power LED is on, green LED does not flash, nothing on display===
''Note: A faintly glowing steady green LED means '''no boot code has ever been executed''', as almost the first thing the boot code does is to turn the faint glow off! When flashing/blinking the green LED should be as bright as the red LED.''

*The Raspberry Pi cannot find a valid image on the SD card. Turn the board over to check that the card is inserted correctly; the insertion force is much larger than for some laptops.
** Check that you have correctly written a Raspberry Pi image to the card by using a MAC or PC and browse for the following files:
*** bootcode.bin
*** fixup.dat
*** start.elf amongst others
** Did you have admin rights when you used the SD-card writer software? Without it the software might go through the motions without actually doing anything!
** Older images do not load boot code for revB boards with the Hynix chip. Use release 2012-02-09 (?) or later. (I observe a single blip on the green activity LED)
** It is also possible that the image you are writing to the card is corrupt, as downloads do occasionally end up corrupted or truncated. You can check with a checksum utility to verify the integrity of the download.

* The SD card may itself have an issue. See [[RPi_VerifiedPeripherals#SD_cards|Known SD Cards]].

*Try with no cables connected except the USB power lead, and SD card inserted. You should see flashing of the OK light for ~20 seconds. If that helps, plug in cables one at a time to identify which is interfering with boot.

*Confirm the USB cable is properly seated in the power slot. The red power LED does not necessarily mean it is fully connected.

*The voltage is too low (below 5 V), try a different power supply and/or cable. The R-Pi needs a supply rated for 700 mA or more. Some supplies labeled as such cannot actually provide their rated current while maintaining 5V. See also, [[#Troubleshooting_power_problems]].

*There may be a bug in the distributed version of bootcode.bin which causes problems with some sdcards. Try this version: https://github.com/raspberrypi/firmware/blob/234c19de7cbaaf4997671d61df20a05759066295/boot/bootcode.bin. Please let us know if it "fixes" your non-working SD card (or, more importantly, if it doesn't). This can also manifest itself as intermittent booting, or only booting when cold.

*''(unlikely)'' hardware abuse, for example by connecting a 7 V supply to a 3v3 GPIO output pin<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=6&t=5096&p=76503#p76503</ref> or powering up the board after a solder splash shorts some traces<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=6&t=5096&p=76654#p76654</ref>.

*Look at the SD card holder on the Raspberry Pi carefully. At first glance it may look fine but the contacts must be springy and they must protrude at least 2mm as measured from the lower edge of the holder to the top of the contact bulge. This happens due to the solder process and the type of holder used. Some of the solder residue falls into the contact cavity restricting the springiness and the height that the contact protrudes. You can fix this yourself but remember you can void your warranty. The contacts are delicate so be carefull. Insert a needle pin under the contact bulge and pull lightly up until the one end of the contact unclips. Clean the cavity where the contact unclipped from of any solder or other residue by blowing into the cavity. Clip the contact back into the cavity by lightly pushing it into the cavity. Do this for all the contacts. Look at these photos. [[Media:SDcardHolder.JPG]], [[Media:UnclipContact.JPG]], [[Media:UnclippedContact.JPG]]
** Ensure that when your SD Card is fully inserted that the longer metal spring contacts (one clearly visible on the end of the slot, and one hidden in the side nearest the power connector) are closed. These are used to detect the presence of an SD Card therefore if no contact is made then the Raspberry Pi won't attempt to access the the card.
** Check carefully for any cracks or damage to the SD Card slot, if the sides are damaged then the card may not be making proper contact with the pins (can usually confirm this if your Raspberry Pi boots if you manually hold the SD Card in position). For ways to resolve this, see [http://pihw.wordpress.com/2013/02/23/occupational-hazards-proudly-protecting-my-poorly-pi-perfectly/ PiHardware - SD Card slot fixes] for more info.

*If for whatever reason the main polyfuse F3 has been overheated previously it may happen that it hasn't completely recovered, in which case, if you turn the PI on, a considerable amount of energy from the power supply is lost in the fuse and doesn't reach the PI. Try if the polyfuse seems hot. For this problem too read [[#Troubleshooting_power_problems]].

*Some problems have been reported if the ambient temperature is low that might be related to micro-fractures, fissures in solder or other issues. Try warming the Raspberry Pi with a hair dryer for just a few seconds (do not use excessive heat or you may cause irreversible damage!) and reconnect the power. Check this video http://www.youtube.com/watch?v=AwF6v-4NFdg

===Green LED blinks in a specific pattern===

According to [http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=8725#p103338 this forum post] the green light will blink in a specific pattern to indicate some types of errors:

* 3 flashes: <tt>loader.bin</tt> not found
* 4 flashes: <tt>loader.bin</tt> not launched
* 5 flashes: <tt>start.elf</tt> not found
* 6 flashes: <tt>start.elf</tt> not launched
* 7 flashes: <tt>kernel.img</tt> not found

Firmware since 20th October 2012 no longer requires loader.bin, and the flashes mean:

* 3 flashes: <tt>start.elf</tt> not found
* 4 flashes: <tt>start.elf</tt> not launched
* 7 flashes: <tt>kernel.img</tt> not found

If start.elf won't launch, it may be corrupt.

===Coloured splash screen===
[[File:Debug-screen.jpg]]

With recent firmware, a coloured splash screen (actually its just four pixels "blown up" by the GPU to full screen) is displayed after GPU firmware (start.elf) is loaded. This should be replaced by linux console a second later.
However if the coloured screen remains, it suggests the kernel.img file is failing to boot. Try replacing it with a known good one.

Immediately after displaying the splash screen, the PI starts consuming a little more current, if the PI resets at that moment its an indication that the power supply isn't able to deliver the full current your PI requires, but dips its output voltage below a minimum when loaded with the full current the PI needs.

===Kernel Panic on boot ===
Text appears on screen, but then hangs with debug messages. This can be caused by USB devices such as keyboards.
Try again with nothing in the USB.

===Raspberry Pi shuts down (or restarts) soon after booting up===
This is caused by a power supply producing too low a voltage. See [[#Troubleshooting_power_problems]].

===Pi boots sometimes but not always===
With a known good power supply and known good SD card, the R-Pi boots occasionally, but other times shows only a tiny green flicker from the "OK" LED and it fails to start, even with no USB devices and no Ethernet. This has been reported several times<ref>http://www.raspberrypi.org/forum/troubleshooting/will-not-boot-consistently-any-suggestions-before-i-send-my-pi-back</ref>
<ref>http://www.raspberrypi.org/forum/troubleshooting/booted-once-wont-work-again</ref>
<ref>http://www.raspberrypi.org/forum/troubleshooting/possible-fault-pi-boots-sometimes-but-not-always</ref> and remains an open issue. Low voltage or an improper SD card can cause it. Some SD cards will work until they warm up slightly, and then fail<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=6&t=5900&p=79008#p79008</ref>. When exposed to 21 C room temperature the warmest part of an uncased working R-Pi should be 41 C<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=6&t=5900&p=78973#p78973</ref>. The wiki has a [[RPi_VerifiedPeripherals#SD_cards | list of working SD cards]]. Buy from a reliable vendor as it has been [http://www.petapixel.com/2011/05/20/one-third-of-the-sandisk-memory-cards-on-earth-are-counterfeit/ claimed] that 1/3 of all "Sandisk" labelled memory cards are counterfeit.
*It could be that the SD memory card is not making proper contact with the Raspberry Pi. Look at the SD card holder on the Raspberry Pi carefully. At first glance it may look fine but the contacts must be springy and they must protrude at least 2mm as measured fron the lower edge of the holder to the top of the contact bulge. This happens due to the solder process and the type of holder used. Some of the solder residue falls into the contact cavity restricting the springiness and the height that the contact protrudes. You can fix this yourself but remember you can void your warranty. The contacts are delicate so be carefull. Insert a needle pin under the contact bulge and pull lightly up until the one end of the contact unclips. Clean the cavity where the contact unclipped from of any solder or other residue by blowing into the cavity. Clip the contact back into the cavity by lightly pushing it into the cavity. Do this for all the contacts. Look at these photos. [[Media:SDcardHolder.JPG]], [[Media:UnclipContact.JPG]], [[Media:UnclippedContact.JPG]]

==Keyboard / Mouse / Input Devices / Webcams==

===R-Pi does not respond to key presses / Keyboard randomly repeats key presses===
''note:during entering the password most linux distro's wont show that you typed in anything (not even "*" characters) this is normal behaviour, try the keyboard while entering the user name!''

This is most often caused by inadequate power. Use a good power supply and a good power cable. Some cheap cables that work with a cell phone, cannot fully power the R-Pi. Some USB devices require a lot of power: most will have a label showing the voltage and mA requirements. They should be 5v 100mA each max, any more than this they must be used with a powered USB hub. Try unplugging every USB device except the keyboard (you should also note that some keyboards have built in hubs and can try to draw 150mA (Pi can only handle 100mA per USB slot without a hub)).
Also, use the latest software. Forum user MrEngman [http://www.raspberrypi.org/forum/absolute-beginners/using-a-powered-usb-port-to-power-a-rpi#p76485 reported] some keyboard repeats and wireless hangs until [http://www.raspberrypi.org/downloads upgrading] to the debian6-19-04-2012 kernel, which he reports stable with no problems even with a low [[R-Pi_Troubleshooting#Troubleshooting_power_problems | TP1-TP2 voltage]] of 4.65 - 4.68 volts.

Some users have reported that their keyboards work fine on Arch linux, but on Debian distro's, their keyboards become erratic (repeats and/or skips key presses). One suggested remedy to this, which has some positive feedback, is to adjust the USB bus speed. To do this, you need to edit the cmdline.txt file, and add "dwc_otg.speed=1" (without quotes) to the end of the file (found in the /boot directory).

Worst case scenario, some (advanced) keyboards, such as the Roccat Arvo, have kernel modules that need activating. If you have access to another keyboard temporarily, you will need to modprobe the relevent driver. Or if this is not possible, you can rebuild the kernel (instructions available on the wiki page) with the modules installed. (to find the drivers for keyboards etc, you need to find "Device Drivers -> hid Devices".)

As a workaround you can use programs kbdrate and xset to tune the keyboard repeat rate:
<pre>
kbdrate -r 2.0 -d 1000
</pre>
on the console and
<pre>
xset -r
</pre>
on the desktop (xset is available with: sudo apt-get install x11-xserver-utils)

===Keyboard / Mouse interferes with USB WiFi device===
Connecting a keyboard and/or mouse while a USB WiFi device is connected, may cause one or both devices to malfunction. On April 30 2012, there was a bugfix<ref>https://github.com/raspberrypi/linux/commit/e09244e60881148431ecd016ccc42f1fa0678556</ref> relating to USB sharing between high-speed (eg. WiFi) and full/low-speed devices (eg. keyboard/mouse). User spennig<ref>http://www.raspberrypi.org/forum/troubleshooting/usb-power-hub-wifi/page-4#p74609</ref><ref>http://www.raspberrypi.org/forum/troubleshooting/success-with-kb-mouse-wifi?value=3761&type=8&include=1&search=1</ref> reports this patch did not fix the Mouse/WiFi conflict. On 2012-05-12, user spennig was pleased to confirm that wifi was working with a USB keyboard and mouse, as long as the Raspberry Pi had a good PSU and a powered hub. Even so, some experimentation was needed, e.g. USB WiFi connected to the device, and the keyboard and mouse connected to the powered hub. Some experimentation may be necessary to find a working combination; however a good power supply is essential.

[[User:ThomasH|My]] experience regarding this issue point to interferences in the 2.4 GHz frequency band in which both WiFi sticks, as well as USB keyboards transmit data. Changing the channel on the wireless access point fixed the problem completely. In my case (Belkin N150 + Logitech K260/M210) I switched from channel 1 to channel 13, which results in a frequency shift of 50 MHz. Possibly enough to not affect the keyboard/mouse receiver.

===Wireless Keyboard trouble===
Some wireless keyboards, for example the Microsoft Wireless Keyboard 800 are reported to fail<ref>http://www.raspberrypi.org/forum/troubleshooting/display-and-keyboard-issues-on-a-real-pi#p74816</ref> even though the current drawn by the wireless adaptor is within the R-Pi USB spec limit of 100 mA. This may be a software driver problem.

===Re-mapping the keyboard with Debian Squeeze===
If different letters appear on-screen from that which you typed, you need to reconfigure you keyboard settings. In Debian, from a command line type:
sudo dpkg-reconfigure keyboard-configuration
Follow the prompts. Then restart your RasPi. '''Or:''' From the command line type:
sudo nano /etc/default/keyboard
Then find where it says <blockquote>XKBLAYOUT=”gb”</blockquote>and change the gb to the two letter code for your country. [http://www.raspberrypi.org/phpBB3/viewtopic.php?p=78325#p78325]

===Slow keyboard mapping===
If you have remapped your keyboard and get a very long delay during the keyboard mapping at startup, type the following once on the command line after you have logged in:
sudo setupcon

===No USB device works, with known good PS, SD card, KB===
There has been more than one report<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=7533</ref><ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?t=5766#p77576</ref><ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?t=5766#p80995</ref> of a R-Pi booting but not getting USB input, using a known-good power supply, SD card, and keyboard. The more common cause for no USB devices working is [[#Troubleshooting_power_problems|low power supply voltage]] from bad PSU, cable, or USB hub, but in this case the problem was no clock signal present at the LAN9512 USB/Ethernet chip "IC3", and the solution was to reflow the solder on the 25 MHz crystal "X1" on the bottom side of the board.
Or return the board for a replacement, but before making this conclusion, confirm known good peripherals. A significant number of
[[RPi_VerifiedPeripherals#USB_Keyboards| USB keyboards]] are not compatible with R-Pi. As of June 1 2012, Eben reported<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=6822&p=89589&hilit=eben#p89513</ref> that only about 1 in 1000 shipped R-Pi boards have been found to have a hardware fault of any kind.

===Webcam===
====guvcview====
<pre>
sudo apt-get install guvcview
</pre>
Use the excellent guvcview program to test your webcam and to change the capture settings. You can improve the frame rate to a great extent by changing the settings.

====hub or internal usb====
It is possible that your camera will only work on an internal usb port and not on the hub.

====freeze====

If you are experiencing freezes or timeout errors while using a webcam this script may help:

<pre>
#!/bin/bash
sudo rmmod uvcvideo
sudo modprobe uvcvideo nodrop=1 timeout=5000 quirks=0x80
</pre>

(quirks=0x80 is a bandwidth quirk, the necessary bandwidth will be estimated by the uvcvideo driver instead of using the one proposed by the camera)

== Updating firmware ==
=== Check your firmware version ===
Using the latest firmware version may help various problems with SD card and display compatibility. Check the kernel version with:
uname -a
Linux RPi 3.1.19 #1 PREEMPT Fri Jun 1 14:16:38 CEST 2012 armv6l GNU/Linux

And the GPU firmware with:
/opt/vc/bin/vcgencmd version
May 31 2012 13:35:03
Copyright (c) 2012 Broadcom
version 317494 (release)

=== Get the latest firmware version ===
The GPU firmware and kernel can be updated with [https://github.com/Hexxeh/rpi-update Hexxeh's rpi-update tool].

However this requires the Pi to be successfully booted. With sdcard problems, you may not get that far, so can try a manual udpate.
If you have a Linux machine, rpi-update can be run on that in an offline mode, and will update your sdcard from the Linux machine.

Otherwise, on a Windows computer, you will see the "/boot" partition appear as the contents of SD card.
You can download the latest GPU firmware version [https://github.com/raspberrypi/firmware/blob/master/boot/start.elf here].
Click on '''view raw''', then save it, and put the new start.elf file on the sdcard replacing the existing one. Similarly, the latest kernel is [https://github.com/raspberrypi/firmware/tree/master/boot/kernel.img here].
After updating these files you should be able to boot. You still need to run rpi-update to update the kernel modules (in /lib/modules) and the GPU libraries (in /opt/vc).

=== Choosing the right ARM/GPU memory split ===
There is a choice of how the 256M/512M of RAM is divided between the ARM and GPU:
gpu_mem=16 : 16M GPU, 240M/496M ARM split : Maximum ARM memory. Good for ARM desktop use. No accelerated video or 3D possible.
gpu_mem=64 : 64M GPU, 192M/448M ARM split : Reasonable ARM memory. Simple video (omxplayer) or 3D (quake) is possible. This is the default.
gpu_mem=128 : 128M GPU, 128M/384M ARM split : Use this for heavy 3D work, or 3D plus video. Needed for XBMC.

To switch, edit the gpu_mem= setting in your config.txt and reboot.

Note: other amounts are also possible, but setting gpu_mem=32 is usually the wrong choice. gpu_mem=16 is almost always a better choice.

Also note that before the release of the 51MB PI a different method was used based on splitting the 256MB RAM in a part for the CPU and GPU. As this noting system was causing trouble if the amount of RAM was not always the same. the above new method was adapted.

Make sure your editor doesn't change the first letter of the line into an uppercase letter, as some editors do. The entry is case sensitive.

== SD cards ==

* If you have problems, check you have latest firmware version (described above)
* Some SD cards do not work on the R-Pi, so check the [[RPi_VerifiedPeripherals#SD_cards|list of known SD cards]].
* If you are having problems setting up your SD card you might want to start by erasing it completely - especially if it has been used elsewhere and still contains data / partitions.
** Windows and Mac users can download a formatting tool from the SD Association: https://www.sdcard.org/downloads/formatter_3/
* Reformatting cards is also easy to do in a digital camera.
* After writing the image to the SD card, verify that you can see the boot partition when you insert the SD card into your computer. The partition should contain a number of files, including ''start.elf'' and ''kernel.img''. If you do not see these files on the SD card, you have made an error writing the image file.
* If you are manually preparing your SD card on Linux or Mac OS using the ''dd'' command, this operation will completely erase any existing data and partitions. Make sure you write to the whole card (e.g. <tt>/dev/sdd</tt>) and not to an existing partition (e.g. <tt>/dev/sdd1</tt>).
* If you have an sdcard that doesn't work with latest firmware, head over [http://www.raspberrypi.org/phpBB3/viewtopic.php?f=63&t=6093 here].
* If you put the SD card into your PC in an attempt to write the R-Pi operating system onto it, and the PC tells you the card is write-protected, even with the write-protect tab in the correct, forward position, then you may have a faulty SD-card rewriter. There's a common fault with many SD-card rewriters - The write-protect tab is detected by a very thin, narrow metal strip, that is part of a switch. When the card is inserted, the write-protect tab is supposed to push the strip and make/break the contact, as needed. Unfortunately, these strips have a habit of getting stuck, because they are mounted in a thin plastic channel, and only need to be deformed slightly sideways to get jammed.
Luckily, if you have this problem, most built-in card readers are easy to pull apart and repair; some users have even reported succesfully unjamming the switch with a blast of compressed air from a can into the SD-card slot without having to dismantle anything.
You may also be able to temporarily get round the problem by putting the write-protect tab in a half-way position - this pushes on a different part of the strip and may break the contact - it's worth trying a few, slightly different positions. You could also use a USB-SD card adaptor, which are cheap to buy.

=== SD(DC|DX] Card Class 6 & 10 Hints ===

[[http://elinux.org/index.php?title=RPiconfig&section=14|SD card usage Hints with OverClocking ]]

==Networking==

===Ethernet connection is lost when a USB device is plugged in===
This is often caused by inadequate power. Use a good power supply and a good power cable. Some cheap cables that work with a cell phone, cannot fully power the R-Pi. Some USB devices require a lot of power (>100 mA), so they must be used with a powered USB hub. Some cheap USB hubs suck power from the Raspberry Pi even if a USB power supply is connected. (More often than not, however, the reverse is true with cheap hubs—the Pi draws just enough power backwards from the powered hub to unsuccessfully attempt booting.)

There is an ongoing issue with the Ethernet connection being lost when low-speed devices, such as mice or keyboards are connected via a powered USB hub. The simplest way to solve this is to connect your mouse and keyboard directly into the 2 USB ports on the R-Pi (assuming they draw less than 100 mA apiece).

===Ethernet connects at 10M instead of 100M===
The LED in the corner of the board labelled "10M" is mislabeled on the rev 1.0 PC board. It is correctly labeled "100" on the rev 2.0 PC board. When that LED is on, RasPi is connected at 100 Mbps. You can confirm the true transfer rate using a network benchmark such as iperf. You can also read the current network speed with:
cat /sys/class/net/eth0/speed

===Cannot ssh in to Pi===

In the Debian image, ssh is disabled by default. Boot commands are taken from /boot/boot.rc if that file present. There is an example file named '''boot_enable_ssh.rc''' that enables ssh. So:

sudo mv /boot/boot_enable_ssh.rc /boot/boot.rc

and reboot should enable ssh. (password as below)

===Network/USB chip gets too hot to touch===

This is normal. In open air at 24 C, the LAN9512 Ethernet/USB chip reaches about 52 C after some time. This is too hot to touch for more than a few seconds, but it is not unusually hot for the chip.

The
[http://www.smsc.com/media/Downloads_Public/Data_Sheets/9512.pdf LAN9512 data sheet] in Table 4.1 on p.40 says it comes in two versions, rated for operation at an ambient temperature in still air (Ta) of 70 C (commercial) or 85 C (industrial). It uses 763 mW at 3.3V with maximum traffic on 100baseT and both USB ports (Table 4.3.4, p. 42).

There is a study of RasPi heat profiles by "Remy" at [http://www.geektopia.es/es/technology/2012/06/22/articulos/se-calienta-el-ordenador-raspberry-pi-estudio-de-sus-temperaturas-en-funcionamiento.html ¿Se calienta el ordenador Raspberry Pi? Estudio de sus temperaturas en funcionamiento] (''Is the Raspberry Pi computer getting hot? A study of its operational temperature.'') The Spanish article has numerous color temperature images of RasPi in various operational modes, with the highest LAN9512 case temperature measured as 64.5 C.

===Networking no longer works when changing SD card between two Raspberry Pis===

In some distributions, /etc/udev/rules.d/70-persistent-net.rules remembers which MAC address is associated with eth0, so each new device will be assigned as a different interface (eth1, eth2, etc.) due to the different MAC addresses. Editing /etc/udev/rules.d/70-persistent-net.rules to remove the invalid rules and rebooting may help fix the problem.

===Crashes occur with high network load===

The USB driver allocates memory from the kernel, and when traffic is very high (e.g. when using torrents/newsgroup downloads) this memory can be exhausted causing crashes/hangs. (Crashes with high network load can also be related to your power supply, try a powered usb hub.) You should have a line like:

vm.min_free_kbytes = 8192

in /etc/sysctl.conf. Try increasing that number to 16384. If that doesn't work, try adding to /boot/cmdline.txt

smsc95xx.turbo_mode=N

which will reduce network throughput, but has improved stability issues for some.

If the above fixes do not work, you can prevent the crashes by limiting the bandwidth (This is also working sometimes if the crashes are related to power supply.):

wondershaper wlan0 1500 1500

This bandwidth (~150k/s) is enough to stream video with flvstreamer and omxplayer.

(wondershaper is available in raspian: sudo apt-get install wondershaper. You could also test limiting the bandwidth in advance with wget --limit-rate=150)

===Network connection fails when a Graphical User Interface is being used===

The network connection may fail when the command startx is used to enter a Graphical User Interface. This is caused by a bug in the USB driver related to certain types of USB mouse.

As of 1 September 2012, this fault is fixed in the latest firmware. To load the latest firmware, see
[http://elinux.org/R-Pi_Troubleshooting#Updating_firmware http://elinux.org/R-Pi_Troubleshooting#Updating_firmware]

==Passwords==
===I do not know the password to login===
Please check the page [http://www.raspberrypi.org/downloads http://www.raspberrypi.org/downloads] for the correct username and password for each image.

Here are the most common username/password combinations:
* Raspian "wheezy" pi/raspberry
*Debian after Feb 2012: pi/raspberry
*Debian 17 Feb 2012: pi/suse
*Arch: root/root
*Bodhi: pi/bodhilinux

===Some programs refuse to accept my password===
While using Debian, some programs may ask for your password but refuse to accept a valid password.

This is a fault in old Debian images previous to September 2012. If you are using an image with this fault, upgrade to a more modern image or enter the following command on the command line.
gconftool-2 --type bool --set /apps/gksu/sudo-mode true
Please enter this command carefully, the spaces are important. The command should be accepted without any response or errors.

===I don't know the root password===

There is no root password set by default on Debian. You are expected to do everything through sudo. You can set one with "sudo passwd root" - just make sure you know what you are doing with a root account.

==Sound==
===Sound does not work with an HDMI monitor===
This is caused by some computer monitors which select DVI mode even if an HDMI cable is connected. This fix may be necessary even if other HDMI devices work perfectly on the same monitor (or TV)!

Edit the configuration file - see the instructions at [[R-Pi_ConfigurationFile]].

Add the following line to the configuration file:
hdmi_drive=2

This will force it to select HDMI mode.

'''More reasons why sound does not work with an HDMI monitor'''

With an HDMI connection it might be possible to hear:
./hello_audio.bin 1
but not:
aplay /usr/share/sounds/alsa/Front_Center.wav

Firstly, it seems that some HD TVs mute audible sound output when there is no digital input, and slowly fade the sound up and down at the start and end of digital input. This means that short duration sounds will not be heard. A work around is to play longer duration wav files.

Secondly, it seems that some HD TVs mute audible sound output when there is only one channel of digital input. So, as the file Front_Center.wav is mono, it might not be heard. ALSA aplay uses the file information header to configure its digital output. And the aplay -c 2 option does not over-ride the settings aplay picks up from the file information header. So, if your HD TV doesn't accept just one channel of digital input, you cannot use aplay to hear a mono wav file. However, with the command speaker-test, the -c2 option does work, and sets 2 channels in the digital stream. So speaker-test can be used to hear the file Front_Center.wav in either the left or right speaker using the -s option 1 or 2.
For example
Speaker-test -c 2 -s 1 -t wav -W /usr/share/sounds/alsa -w Front_Center.wav
should be heard on the left speaker. But note that the command speaker-test seems only to like mono wav files, and seems not to play stereo wav files.

The command aplay plays 2 channel stereo wav files in stereo sound without problem (provided they last longer than the time it takes the TV to unmute and remute). A helpful example I found is the stereo file LRMonoPhase4.wav at the Kozco web site [http://www.kozco.com/tech/soundtests.html]

===Sound does not work at all, or in some applications===
Enter the command 'alsamixer' and use the control to check that the volume is up (arrow keys) and that the output is not muted (M key).

In Debian Squeeze, sound is disabled by default because the ALSA sound driver is still "alpha" (not fully tested) on the R-Pi. To install support for sound, type the following from a command line (from the command prompt ''before'' "startx" or in a terminal window)

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install alsa-utils
sudo modprobe snd_bcm2835

On Debian Wheezy, snd_bm2835 is enabled by default, so the 'modprobe' step is not necessary. Next try:

aplay /usr/share/sounds/alsa/Front_Center.wav

By default output will be automatic (hdmi if hdmi supports audio, otherwise analogue). You can force it with:

amixer cset numid=3 <n>

where n is 0=auto, 1=headphones, 2=hdmi.

If you have pulseaudio installed you need to also specify the card number:

amixer -c 0 cset numid=3 <n>

With recent firmware, you can build hello_audio with:
cd /opt/vc/src/hello_pi/
./rebuild.sh
cd hello_audio

With older firmware
cd /opt/vc/src/hello_pi/hello_audio
make

to test analogue output:
./hello_audio.bin
and:
./hello_audio.bin 1
to test HDMI.

Also note that you may have to add your user to the 'audio' group to get permission to access the sound card.

Following this setup, you should be able to play wav files with the command

aplay "my file.wav"
Other command features can be found with
aplay --help
You will find numerous test files under /usr/share/scratch/Media/Sounds/ .

===Removal of installed pulseaudio===
Between December 2012 and February 2013 the standard raspbian wheezy distribution, and apt-get upgrade, included pulseaudio. Forum posts suggest that pulseaudio can break alsa. Whilst some members identify various workarounds, others find only removal of pulseaudio restores sound output.
sudo apt-get --purge remove pulseaudio

===Playing MP3 files===
The alsa app included in the standard distribution plays wav files. If you want to play mp3 files, do the following to install an mp3 player (after installing alsa-utils):

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install mpg321

You can play mp3 files with the command

mpg321 "my file.mp3"

Other command options can be determined with
mpg321 --help
The mp3 support with this app is complete but not robust.

==Display==
===Startx fails to start===
If you just get errors instead of a desktop when typing
startx
you may be out of storage space on the SD card. By default there are only a few hundred MB free in the 2 GB main partition, which can quickly fill up if you download files. Make sure there is some space free (gparted can expand a partition, if the SD card is > 2GB). Also, installing some software may incorrectly create or modify a .Xauthority file in your home directory, causing startx to fail, according to [http://www.raspberrypi.org/forum/troubleshooting/startx-fails-worked-yesterday this thread]. Temporarily renaming, moving, or deleting that file may fix the problem.

===Screen is the wrong color===
Check and see if the DVI cable is screwed in properly. If that doesn't work then try [[#Interference_visible_on_a_HDMI_or_DVI_monitor|this]] section.

===Video does not play or plays very slowly===
The only hardware-accelerated video player is in the [http://www.raspberrypi.org/forum/general-discussion/openelec-meets-raspberry-pi-part-1-xbmc XBMC distribution] and its command line variant [[omxplayer]]. H264 is the only hardware-accelerated codec, for playback. No hardware encoding is supported. Additional codecs were not purchased as licensing fees would have increased the R-Pi's price.

===Can only get 800x480 resolution in LXDE (Arch linux)===
Known issue with distro package as of 17th April 2012 - there's some missing boot config information. Creating a suitable cmdline.txt fixes it - type the following at the Raspberry Pi command line:

<pre>
sudo echo "dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 root=/dev/mmcblk0p2 rootfstype=ext3 rootwait" >/boot/cmdline.txt
</pre>

===Big black borders around small image on HD monitors===

Out of the box, R-Pi graphics don't necessarily fill the whole screen. This is due to something called "Underscan", and it can be fixed easily.

Note: the best solution is to disable overscan on the TV/monitor. Check the display menu options (it may be called "just scan", "screen fit", "HD size", "full pixel", "unscaled", "dot by dot", "native" or "1:1"), then use the disable_overscan=1 option.

Edit the configuration file, see the instructions at [[R-Pi_ConfigurationFile]].

Add the following lines to the configuration file...

If your display has no overscan:

<pre>

disable_overscan=1

</pre>

or if your display has some overscan:

<pre>

overscan_left=-20

overscan_right=-20

overscan_top=-20

overscan_bottom=-20

</pre>

Making the R-Pi graphics fill the screen is a matter of experimenting with the numbers you put in the config.txt file. Change the numbers – try jumps of 5 or 10 at a time. Bigger negative numbers reduce the black borders (so -40 means less black border than -20). The numbers do not all have to be the same; you can use this feature to centre the display on the screen.

This only affects the framebuffer (e.g. console or X). It doesn't affect hardware layers (like video/3D). You can make it apply to hardware layers with:

<pre>
overscan_scale=1
</pre>

===Writing spills off the screen on HD monitors===

Out of the box, R-Pi graphics may be larger than the 1080p (ie Full HD) screen. This is due to something called "Overscan", and it can be fixed easily by creating a simple text file on the R-Pi SD card by using Notepad on your PC.

Follow the instructions in the section "Big black borders around small image on HD monitors", but use positive numbers for the overscan settings, for example
<pre>

overscan_left=20

overscan_right=20

overscan_top=20

overscan_bottom=20

</pre>

===Interference visible on a HDMI or DVI monitor===
This may be caused by loss of signal on long video cables. The signal level may be increased by changing a configuration parameter.

[[File:RPi_HDMI_interference.jpg|600px]]

Edit the configuration file, see the instructions at [[R-Pi_ConfigurationFile]].

Add the following line to the configuration file
config_hdmi_boost=4

You may experiment with different values of config_hdmi_boost. Value 1 is used for very short cables, value 7 is used for very long cables. At your own risk, you can go up to 11, but risk frying a sensitive monitor.

Note that various adapters, such as HDMI-to-DVI, can also cause power loss and therefore require high values of config_hdmi_boost even with short cables.

This option can also help when there is no display output at all, the display periodically blanks, or colours are wrong/inverted.

This symptom can also be caused by RasPi +5V (measured from TP1 to TP2) falling too low. See [[#Troubleshooting_power_problems|Troubleshooting Power Problems]].

===No HDMI output at all===
[[File:GPIOs.png|thumb|200px|right|The PI's GPIO header P1 [https://sites.google.com/site/burngatehouse/home/drawings/GPIOs2.gif Source] ]]
First make sure the display is powered on and switched to the right input before booting Pi.

If you have the [http://www.raspberrypi.org/archives/1435 Rasbian Wheezy] image (recommended) then try
hdmi_safe=1
Which will force the PI to boot in "safe mode".

For a quicker way to force wheezy into booting in safe mode, which doesn't need editing config.sys, you can also try to boot while holding the GPIO header P1-pin-5 (GPIO 1, SCL) low. This pin is normally held high with a pullup, but if you place a jumper between pin 5, (GPIO 1) and pin 6, (GND) of the GPIO header it will force the PI to boot in safe mode, which will force a 640x480 VGA screen mode, which any HDMI device should be able to display. Be very careful not to connect any other pins, especially not pins 1 and 2 (3V3 and 5V) as doing so, with power on, will damage your PI!

Otherwise, try adding the following line to the configuration file (similar to interference case above)
config_hdmi_boost=4

Your monitor/cable may not be asserting the hotplug signal. You can override this with:
hdmi_force_hotplug=1

A similar problem has occured following the installation of [http://www.raspberrypi.org/downloads Rasbian Wheezy image] "2013-02-09-wheezy-raspbian" - the hotplug signal appeared to be no longer detected when a [http://www.cpmspectrepi.webspace.virginmedia.com/raspberry_pi/MoinMoinExport/HDMI3PortSwitcher.html HDMI 3 Port Switcher] was in use for the Pi running from that image. An older, but updated and upgraded image still worked, as did a similar image on the other Pi connected to the switch, but, unless the above override was implemented, the Pi with the new image would only provide a HDMI display when '''directly''' connected to the monitor. The same problem has re-occurred when using that wheezy image with a new (in March 2013) "Model A" Pi.

Also [http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=7513 try] the following video options:
hdmi_group=2
hdmi_mode=4
which resolved an issue with DVI monitor reporting "input signal out of range"

As a last resort, try deleting (rename to keep backup) config.txt from the SD card.

Also check that the RasPi +5V voltage (measured from TP1 to TP2) is in the correct range. One user found that his DVI-D monitor blanked out when +5V was too low. See [[#Troubleshooting_power_problems|Troubleshooting Power Problems]].

Here's a rare cause: A standard HDMI cable has five individual ground wires plus a shield. Some cheap HDMI cables do not implement the individual grounds and just have a common foil shield that's connected to the HDMI plug shells at both ends. This works OK in most HDMI applications since most HDMI sources (like RasPi) and most monitors connect the shells to circuit ground. However, some HDMI or DVI monitors may requires individual ground lines. You can tell if an HDMI cable implements the individual grounds by checking for continuity using an Ohmmeter or multimeter. You can find the HDMI pinout for full-size connectors at [http://en.wikipedia.org/wiki/HDMI Wikipedia].

===Composite displays no image===
The output display will default to HDMI if a HDMI display is connected, and composite if not. Make sure there isn't a HDMI cable connected when you want to use composite output.

Also, check that your TV is set to the correct input, normally marked "AV". If your TV has multiple AV inputs, try all of the inputs, normally by pressing a button marked "AV" or "Input" or "Source" or "->O" on the remote control.

===Composite displays only black and white image===
The composite display defaults to NTSC (American) output. Most TVs will show an image with that, but older PAL (European) televisions may display only back and white or no image. To fix this:

Edit the configuration file, see the instructions at [[R-Pi_ConfigurationFile]].

Add the following line to the configuration file
sdtv_mode=2

(You can try other values: 0 is NTSC, 1 is Japanese NTSC, 2 is PAL, 3 is Brazilian PAL)

===HDMI -> VGA adapters===
Some good information can be found here:
* [[RPi_VerifiedPeripherals#HDMI-.3EVGA_converter_boxes]]
* [http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=9819 (RPi forum) Serious HDMI Problems. What's that smell? Burning Raspberry!]

A commonly used adapter from Ebay: gallery with detailed images & steps of a modification to use external power source: [http://imgur.com/a/sLogs/all HERE] --''by [[User:Pinoccio|Pinoccio]]''

==GPIO==
Remember that the GPIO pins are 3.3V logic level only, and are NOT 5V tolerant.

If you momentarily shorted the two end GPIO pins together (+3.3V and +5V), or a supply pin to ground, and the Pi appears to be dead, don't panic. The input polyfuse may have tripped. It is self-resetting after it cools down and the polymer re-crystallizes, which can take several hours. Set the Pi aside and try again later.

The GPIO pins connect directly into the core of the ARM processer, and are static-sensitive, so you should avoid touching the pins wherever possible. If you are carrying a static charge, for example by taking off an acrylic pullover, or walking across a nylon carpet, touching the GPIO pins could destroy your R-Pi, so always earth yourself before touching the pins or anything connected to them.

==General==
===The time is incorrect===
If the clock is off by a series of hours, in the command line type:
sudo dpkg-reconfigure tzdata

The R-Pi has no real-time clock, so unless it can access a timeserver over the network at boot, or time is manually entered by the user, the time/date will restart counting from the last logged time in the previous session.

===A part broke off===

The silver cylinder near the microUSB power input is a 220 uF capacitor ("C6" on schematic). It sticks up and due to the small surface-mount pads, it is easy to break off; several people have done so. This is a power supply filter capacitor which reduces any noise and spikes on the input +5V power. If you like, you can solder it back on, or just leave it off. If you do solder it back on, take care to observe the correct polarity with the black stripe towards the board edge. This part, C6 is a "just in case" component which is good design practice to include, but [http://www.raspberrypi.org/phpBB3/viewtopic.php?f=2&t=4926| as it turns out] most power supplies still work OK without this part installed. This part is also [http://elinux.org/RPi_Hardware#Capacitor_C6 discussed here].

===Unable to install new software===
When trying to install a software package (using the command sudo apt-get install xxxx) you may see the error
Package yyyy is not available
This means that your software list is out of date. Before attempting to install software, you should always make sure that you are using the latest software list by using the commands
sudo apt-get update
sudo apt-get upgrade

==Troubleshooting power problems==

If you think you have a problem with your power supply, it is a good idea to check the actual voltage
on the Raspberry Pi circuit board. Two test points labelled TP1 and TP2 are provided on the circuit board
to facilitate voltage measurements.

Use a multimeter which is set to the range 20 volts DC (or 20v =). You should see a voltage between 4.75 and 5.25 volts. Anything outside this range indicates that you have a problem with your power supply or your power cable.

If you have not used a multimeter before, see these [[http://www.sparkfun.com/tutorials/202 basic instructions]]

Note: Even if the multimeter shows the correct voltage, you may have some power supply problems. A multimeter only displays the average voltage. If there are very short-lived dips or spikes in the voltage, these will not be shown by the multimeter. It is best to measure voltage when Pi is busy.

If your voltage is low, it could be:
* The power supply produces too low a voltage
* The power supply cannot supply enough current, which results in a voltage drop. Make sure Power supply is labelled as at least 700mA. (Some cheap power supplies don't deliver what is labelled).
* The Micro USB power cable is low quality. Some Micro USB cables have very thin conductors, resulting in enough voltage drop for RasPi to fail even if the power supply itself is fine. For details, see [[On_the_RPi_usb_power_cable]].
* Attached USB devices want too much power. The Pi is only designed for up to 100mA USB devices. A USB device wanting more that that will cause a voltage drop.
* The F3 Polyfuse could be blown or bad, see below for how to test.
Note: keyboards with LCD displays, built in USB hubs, backlights, etc are likely to be problematic. Try to use a basic one. Wifi dongles are also unlikely to work when directly connected. Connect high powered USB devices to a powered USB hub.

Try booting without HDMI, ethernet or USB deviced plugged in, and see if the voltage improves.
See also: [[RPi_Hardware#Power_Supply_Problems| Power Supply Problems]]

[[File:RPI_Test_Points.JPG|400px]] [[File:Voltmeter.JPG|250px]]

'''How to test the F3 polyfuse<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=26&t=22318</ref>'''

# Remove all the things plugged into your Raspberry Pi, including SD card.
# Locate the TP2 test point on the top of the board.
# Turn your board over and find the TP2 test point on the bottom of the board. One lead of your multi-meter will always be on the TP2 point on the bottom of the board for all tests.
# Plug your power supply into the micro usb port and power your board.
# Place one lead of your multi-meter on the TP2 point on the bottom of the board and one lead on the side of the F3 fuse closest to the edge of the board. Note the voltage. This is the voltage coming into your RPi from your power supply.
# Keeping one lead on TP2, move the other lead to the side of F3 closest to the SD card slot. This is the voltage coming out of the F3 fuse.

[[File:F3-testing.jpg|none|frame|Multi-meter lead placement for testing the Raspberry Pi F3 Polyfuse]]

If the voltage is different by more than about 0.3v you probably have an issue with the F3 fuse<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=24005&p=222526#p222526</ref>.

When polyfuses "blow" their resistance increases dramatically, there by limiting the voltage that can pass through them. If your power problem suddenly appeared after your board was known to be working fine, it is probable the fuse is just "blown" and will return to normal. Polyfuses recover from the tripped state to near their normal value in a few minutes, but do take some hours to fully recover so leave it unpowered and check it again in a little while.<ref>http://www.raspberrypi.org/phpBB3/viewtopic.php?f=28&t=24005&p=222549#p222543</ref> If your power problem has been since the first time you plugged in your board, the fuse was probably bad when it arrived and should be returned to place you purchased it.

Also, on a related issue, do note that if you do not power the PI in the "official manner", that is through it's micro-USB port, but use any alternative way (such as through the GPIO header, the test points TP1 and TP2), but also by back-powering it, '''you are actually bypassing the PI's input polyfuse protection device!''' This can have extreme consequences if ever you manage to put more than 6V on the PI, even for a very short period. As this causes the overvoltage device D17 on the the PI to trigger and short the 5V supply! Without the polyfuse limiting the current through D17, it will burn out, probably melting the PI's enclosure with it, (if you have any) and possibly causing a fire-hazard. It will probably also create a permanent short of the 5V supply! So be warned, and if you use back power make sure your hub or its PSU has a fuse to prevent this from happening. If not, add your own fuse.

If you prefer to make your own PSU - see: [[RPi_5V_PSU_construction| Power Supply construction - HowTo]]

==Hardware versions/revisions==
Several different boards have been found probably from different assembly lines, and the following tables try to help you identify your board for better troubleshooting.

Look for the date of manufacturing printed with the year and week. In this example year (2012) and week (18th):[[File:Date_of_manufacturing.jpg|200px|thumb|right]]

For what we can see for model B boards there are mainly two versions that differ on the type RAM used, Samsung (S) and Hynix (H).

For '''Board ver'''. we used: <model><RAM Maker><production date> (ex.: BS1218 is "Model B, Samsung RAM, 18th week of 2012")

Model A:
{| border="1" class="wikitable"
|-
! Board
ver.
! RAM
Chip
! USB
Chip
! Front
! Back
|-
|
|
|
|
|
|}

Model B:
{| border="1" class="wikitable"
|-
! Board
ver.
! RAM
Chip
! USB
Chip
! Front
! Back
|-
| BS12xx
| Samsung
| SMSC
| [[File:RaspberryPi-Board_A-Front.JPG|200px|thumb|center]]
| [[File:RaspberryPi-Board_A-Back.JPG|200px|thumb|center]]
|-
| BH12xx
| Hynix
| SMSC
| [[File:RaspberryPi-Board_B-Front.JPG|200px|thumb|center]]
| [[File:RaspberryPi-Board_B-Back.JPG|200px|thumb|center]]
|}

<big>See a '''complete list''' and user feedback here: [[RaspberryPi Boards]]</big>

=References=
<references/>

{{Template:Raspberry Pi}}

[[Category:RaspberryPi]]

TheMagPiGit

2013-03-26T09:25:33Z

Meltwater: /* Tools for LINUX or OSX */

TheMagPi

2013-03-19T11:10:28Z

Meltwater: /* Raspberry Pi Community Driven */ - added section

{{TheMagPiHeader}}

== Overview ==

[http://www.themagpi.com/ The Mag Pi] magazine is written by the Raspberry Pi community for the community. The authors, layout team and editor come from teaching, IT industry and other professions, based worldwide.

The aim of the magazine is given in detail on [http://www.themagpi.com/en/about/ the Mag Pi web site].

== Driven By The Raspberry Pi Community ==
The MagPi is a community magazine so we welcome all assistance, in whatever form your can provide.

See the above headers for more details, new volunteers should take a look at the Authors section which explains the whole process and how to get started with Writing, Layouts and Proofreading. If something isn't clear, or you need more information, then please get in contact.

TheMagPi

2013-03-19T11:09:57Z

Meltwater:

{{TheMagPiHeader}}

== Overview ==

[http://www.themagpi.com/ The Mag Pi] magazine is written by the Raspberry Pi community for the community. The authors, layout team and editor come from teaching, IT industry and other professions, based worldwide.

The aim of the magazine is given in detail on [http://www.themagpi.com/en/about/ the Mag Pi web site].

== Raspberry Pi Community Driven ==
The MagPi is a community magazine so we welcome all assistance, in whatever form your can provide.

See the above headers for more details, new volunteers should take a look at the Authors section which explains the whole process and how to get started with Writing, Layouts and Proofreading. If something isn't clear, or you need more information, then please get in contact.

RPi MagPi InfoForAuthors

2013-02-06T14:17:11Z

Meltwater: /* Setting Up Scribus */

{{TheMagPiHeader}}
* [[RPi_MagPi_InfoForAuthors|Information for authors]] - the process of submitting an article.
* [[TheMagPiLayout|Layout & fonts]] - description of the standard layout and associated fonts.
* [[TheMagPiPdf|PDF creation]] - instructions for the generation of PDF for electronic and paper publication.

== Instructions for authors ==

The [http://www.raspbian.org/ Raspbian] (Debian Wheezy) version of [http://www.scribus.net/canvas/Scribus Scribus] is used for the [[TheMagPiLayout]]. Articles can be submitted using the Raspbian/Debian version of Scribus or any other format. Articles can be submitted to the editor (editor@themagpi.com).

=== General Tips ===
Here are a few points to remember:
* '''Keep it brief.'''
A typical 2 Page article with images contains around 700 words, the text is purposely kept large (14pt FreeSans Font) to aid reading on various devices and print sizes. We aim to keep most articles within 2 page or less, if longer it can always be split into a series of articles.

* '''Remember beginners will read it.'''
Where possible explain specific terminology and assume the reader is unfamiliar with your chosen topic. Also remember that people will have different setups, so consider testing your instructions on a clean image (if applicable) and consider differences such as Rev1 and Rev2 boards.

* '''Make use of the Template'''
If you are able to, consider using the Scribus Template, this forms the basis of all the articles we produce in the magazine. Variations on the format are fine, but it is a good starting point to obtain what we expect. See section below for details.

* '''Provide Graphics and Images.'''
Where possible obtain suitable graphics and images. Note all images, photos and graphics MUST be free for commercial use (please flag to us beforehand any items you are unsure about).

* '''Work with us.'''
Keep in contact and let us know if you are writing something specific, the content of the next issue is usually allocated quickly so it is helpful to know in advance the topic area and estimates of how long it will take you to produce the article.

Make sure you keep us updated if it is targeted for a specific issue. Often an early draft can help give us a headstart with graphics, layout, proofreading and feedback, so that the article is ready in time.

* '''Don't panic!'''
It is common not to know where to start when writing an article, my advice is to start with writing out what you aim to achieve in the article and why are you writing it (this may not end up in the final article, but it helps focus what you are doing).

* '''Ask for Help.'''
'''Out of Ideas?''' Working on the magazine, we all have 1000s of ideas for articles, but very little time to produce them, so if you want to write but not sure what about, then we can probably give you some ideas (simply let us know what topics you are interested in!).

'''Stuck on something?''' Chances are we may be able to help, or do some testing if required.

'''Need graphics?''' The team can help source and produce graphics if you are unable to obtain suitable ones.

'''Unsure about layouts?''' The article will go through the layout team before publishing, so have a go and if you aren't happy ensure we have enough time to let the layout team work on it.

* '''Enjoy it!'''
Try to pick something you are passionate about sharing with the world. It is an amazing feeling when you see your article published at the end of the month.

=== Setting Up Scribus ===
Using the latest Debian image, Scribus can be installed from terminal:
sudo apt-get install scribus

Authors should use the MagPi Scribus template (found on the [[TheMagPiLayout]] page).

==== Installing Additional Fonts ====

Run the following commands to install standard windows fonts on the Raspberry Pi
(Note: It is recommended the fonts suggested in the template are used).

sudo apt-get install ttf-mscorefonts-installer
sudo dpkg-reconfigure ttf-mscorefonts-installer

=== Timescales & Deadlines ===
While we currently do not have a fixed deadline for articles it is worth remembering the stages we go through:

====Day 1-2 - The magazine content is agreed upon by the Team.====
Articles submitted or suggested after this point are likely to be put in following issues. Usually we have the outline of the content (and then order) worked out in the first few days of the month. We also review how the team got on in the previous month and what we can improve next month.

''Completion Action: Bare-bones version of the magazine is put on Issuu with article place-holders.''

====Week 1 - Prepare Articles====
Authors contacted to ensure articles will be ready. Work with authors to ensure content is in suitable format for use, including graphics and layout (please submit early if help is needed - do not under-estimate how long it takes to prepare graphics and layout).

''Completion Action: Everyone has a good idea of what they need to do and when.''

====Week 2 - Article Drafts Received, Layout & Testing Started====
We aim to start uploading completed/draft articles on to Issuu by this week. Additional work may be required with layout and graphics but full content is required. The status of the planned articles will be reviewed and replacements considered if content is not likely to be ready in time/testing shows issues.

''Completion Action: Draft articles should appear on the Issuu Live Draft''

====Week 3 - All Articles Posted For Proofreading====
By this stage we should have all the articles in the draft of the magazine live on Issuu.

''Completion Action: Completed articles should appear on the Issuu Live Draft''

====Week 4 - Final Proof and Checking====
All input from the authors should now be finished, any changes which impact layout etc probably won't be accepted. All eyes are on the articles and everyone is encouraged to highlight any errors, typos, problems with the articles as quickly as possible so that we can fix them.

''Completion Action: The Issuu Live Draft updated frequently with proof-reading feedback''

====Last Day of Month - Magazine is Completed====
The magazine is released either that night or the following day. Then we start all over!

''Completion Action: Release and look through what has been managed in a month!''

TheMagPiSponsors

2013-02-02T22:33:27Z

Meltwater: /* Commercial sponsors */

{{TheMagPiHeader}}

== Donating Money ==

An obvious way to help the magazine is to donate towards the running costs of the magazine. There are lots of costs involved with running the site and maintaining the magazine and additional funds will allow us to expand the project to reach more readers.

A paypal donate button is on the main page of the [http://www.themagpi.com/ MagPi site].

== Commercial sponsors ==

The MagPi magazine have worked with [http://www.tandyonline.co.uk/ Tandy], [https://www.modmypi.com/ ModMyPi], [http://www.quick2wire.com/ Quick2Wire], [http://www.pibow.com/ Pimoroni Ltd] and [http://www.adafruit.com/ Adafruit].

From issue 9, the MagPi magazine carries several [[TheMagAdvertising|advertising pages]] which are available for rental to companies connected with the Raspberry Pi community.

TheMagAdvertising

2013-01-10T12:25:20Z

Meltwater: /* Terms */

{{TheMagPiHeader}}

From issue 9 onwards, one to four pages of advertisements will be included in each MagPi issue. These advertisements should be to the benefit of the Raspberry Pi community and be written with the same ethos as other articles, to encourage others to learn and develop programming skills.

== Pricing ==

The cost of the advertising space is a function of the number of downloads or printed copies sold.

For issue 9, a full page of advertising space costs 250 pounds (GBP). Half-pages are also available (contact for pricing).

Please contact the editor for further information.

== Translations ==

The magazine may be translated into a number of languages, including:
* French
* German
* Chinese

There are three options:
# The advert can be included in English (this will be done unless requested otherwise).
# Provide a translation of the advert to include (our translators may be able to assist with this - however it will be up to you to verify the accuracy of the translation).
# On request, the advert can be removed from the translated magazine.

Currently, there is no extra cost to include your advert in the translated editions.

== Suitability ==

The magazine is targeted at all ages, so we consider all content and adverts should be similarly suitable and in-offensive.

If we feel something isn't suited, we shall aim to work with the advertiser to resolve any issues.

== Print Deadline ==

Adverts should be submitted as soon as possible, so that they can be included in the Live Draft (typically available from the first week of the month, unless requested otherwise).

Latest submission of the advert should be by 15th of each month, to allow time for layout if required and proofing.

== Terms ==
As with the articles, the advert should not include content which violates copyright or restrict our rights to print and distribute the magazine.

== Sponsored Articles ==
In addition, to traditional adverts, there is an option to write and submit a sponsored article.

This a great way for a company to showcase their in-house expertise by allowing employees to produce an article supported by the company.

Past examples:
# "In-Circuit" series sponsored by Tandy (Issues 2-4)
# "PiGauge" article sponsored by NTS (Issue 8)

The costs involved are much less since you are also providing useful content to the readers.

Please contact the editor for further information.

TheMagAdvertising

2013-01-10T12:24:56Z

Meltwater: Added extra info.

{{TheMagPiHeader}}

From issue 9 onwards, one to four pages of advertisements will be included in each MagPi issue. These advertisements should be to the benefit of the Raspberry Pi community and be written with the same ethos as other articles, to encourage others to learn and develop programming skills.

== Pricing ==

The cost of the advertising space is a function of the number of downloads or printed copies sold.

For issue 9, a full page of advertising space costs 250 pounds (GBP). Half-pages are also available (contact for pricing).

Please contact the editor for further information.

== Translations ==

The magazine may be translated into a number of languages, including:
* French
* German
* Chinese

There are three options:
# The advert can be included in English (this will be done unless requested otherwise).
# Provide a translation of the advert to include (our translators may be able to assist with this - however it will be up to you to verify the accuracy of the translation).
# On request, the advert can be removed from the translated magazine.

Currently, there is no extra cost to include your advert in the translated editions.

== Suitability ==

The magazine is targeted at all ages, so we consider all content and adverts should be similarly suitable and in-offensive.

If we feel something isn't suited, we shall aim to work with the advertiser to resolve any issues.

== Print Deadline ==

Adverts should be submitted as soon as possible, so that they can be included in the Live Draft (typically available from the first week of the month, unless requested otherwise).

Latest submission of the advert should be by 15th of each month, to allow time for layout if required and proofing.

== Terms ==
As with the articles, the advert should not include content which violates copyright or restricts our rights to print and distribute the magazine.

== Sponsored Articles ==
In addition, to traditional adverts, there is an option to write and submit a sponsored article.

This a great way for a company to showcase their in-house expertise by allowing employees to produce an article supported by the company.

Past examples:
# "In-Circuit" series sponsored by Tandy (Issues 2-4)
# "PiGauge" article sponsored by NTS (Issue 8)

The costs involved are much less since you are also providing useful content to the readers.

Please contact the editor for further information.

RPi MagPi InfoForAuthors

2012-12-12T12:43:20Z

Meltwater: /* Week 4 - Final Proof and Checking */

== Instructions for authors ==

The [http://www.raspbian.org/ Raspbian] (Debian Wheezy) version of [http://www.scribus.net/canvas/Scribus Scribus] is used for the [[TheMagPiLayout]]. Articles can be submitted using the Raspbian/Debian version of Scribus or any other format. Articles can be submitted to the editor (editor@themagpi.com).

=== General Tips ===
Here are a few points to remember:
* '''Keep it brief.'''
A typical 2 Page article with images contains around 700 words, the text is purposely kept large (14pt FreeSans Font) to aid reading on various devices and print sizes. We aim to keep most articles within 2 page or less, if longer it can always be split into a series of articles.

* '''Remember beginners will read it.'''
Where possible explain specific terminology and assume the reader is unfamiliar with your chosen topic. Also remember that people will have different setups, so consider testing your instructions on a clean image (if applicable) and consider differences such as Rev1 and Rev2 boards.

* '''Make use of the Template'''
If you are able to, consider using the Scribus Template, this forms the basis of all the articles we produce in the magazine. Variations on the format are fine, but it is a good starting point to obtain what we expect. See section below for details.

* '''Provide Graphics and Images.'''
Where possible obtain suitable graphics and images. Note all images, photos and graphics MUST be free for commercial use (please flag to us beforehand any items you are unsure about).

* '''Work with us.'''
Keep in contact and let us know if you are writing something specific, the content of the next issue is usually allocated quickly so it is helpful to know in advance the topic area and estimates of how long it will take you to produce the article.

Make sure you keep us updated if it is targeted for a specific issue. Often an early draft can help give us a headstart with graphics, layout, proofreading and feedback, so that the article is ready in time.

* '''Don't panic!'''
It is common not to know where to start when writing an article, my advice is to start with writing out what you aim to achieve in the article and why are you writing it (this may not end up in the final article, but it helps focus what you are doing).

* '''Ask for Help.'''
'''Out of Ideas?''' Working on the magazine, we all have 1000s of ideas for articles, but very little time to produce them, so if you want to write but not sure what about, then we can probably give you some ideas (simply let us know what topics you are interested in!).

'''Stuck on something?''' Chances are we may be able to help, or do some testing if required.

'''Need graphics?''' The team can help source and produce graphics if you are unable to obtain suitable ones.

'''Unsure about layouts?''' The article will go through the layout team before publishing, so have a go and if you aren't happy ensure we have enough time to let the layout team work on it.

* '''Enjoy it!'''
Try to pick something you are passionate about sharing with the world. It is an amazing feeling when you see your article published at the end of the month.

=== Setting Up Scribus ===
Using the latest Debian image, Scribus can be installed from terminal:
sudo apt-get install scribus

Authors should use the MagPi Scribus template (found on the [[TheMagPiLayout]] page).

=== Timescales & Deadlines ===
While we currently do not have a fixed deadline for articles it is worth remembering the stages we go through:

====Day 1-2 - The magazine content is agreed upon by the Team.====
Articles submitted or suggested after this point are likely to be put in following issues. Usually we have the outline of the content (and then order) worked out in the first few days of the month. We also review how the team got on in the previous month and what we can improve next month.

''Completion Action: Bare-bones version of the magazine is put on Issuu with article place-holders.''

====Week 1 - Prepare Articles====
Authors contacted to ensure articles will be ready. Work with authors to ensure content is in suitable format for use, including graphics and layout (please submit early if help is needed - do not under-estimate how long it takes to prepare graphics and layout).

''Completion Action: Everyone has a good idea of what they need to do and when.''

====Week 2 - Article Drafts Received, Layout & Testing Started====
We aim to start uploading completed/draft articles on to Issuu by this week. Additional work may be required with layout and graphics but full content is required. The status of the planned articles will be reviewed and replacements considered if content is not likely to be ready in time/testing shows issues.

''Completion Action: Draft articles should appear on the Issuu Live Draft''

====Week 3 - All Articles Posted For Proofreading====
By this stage we should have all the articles in the draft of the magazine live on Issuu.

''Completion Action: Completed articles should appear on the Issuu Live Draft''

====Week 4 - Final Proof and Checking====
All input from the authors should now be finished, any changes which impact layout etc probably won't be accepted. All eyes are on the articles and everyone is encouraged to highlight any errors, typos, problems with the articles as quickly as possible so that we can fix them.

''Completion Action: The Issuu Live Draft updated frequently with proof-reading feedback''

====Last Day of Month - Magazine is Completed====
The magazine is released either that night or the following day. Then we start all over!

''Completion Action: Release and look through what has been managed in a month!''

RPi MagPi InfoForAuthors

2012-12-12T12:41:26Z

Meltwater: -added timeline details

== Instructions for authors ==

The [http://www.raspbian.org/ Raspbian] (Debian Wheezy) version of [http://www.scribus.net/canvas/Scribus Scribus] is used for the [[TheMagPiLayout]]. Articles can be submitted using the Raspbian/Debian version of Scribus or any other format. Articles can be submitted to the editor (editor@themagpi.com).

=== General Tips ===
Here are a few points to remember:
* '''Keep it brief.'''
A typical 2 Page article with images contains around 700 words, the text is purposely kept large (14pt FreeSans Font) to aid reading on various devices and print sizes. We aim to keep most articles within 2 page or less, if longer it can always be split into a series of articles.

* '''Remember beginners will read it.'''
Where possible explain specific terminology and assume the reader is unfamiliar with your chosen topic. Also remember that people will have different setups, so consider testing your instructions on a clean image (if applicable) and consider differences such as Rev1 and Rev2 boards.

* '''Make use of the Template'''
If you are able to, consider using the Scribus Template, this forms the basis of all the articles we produce in the magazine. Variations on the format are fine, but it is a good starting point to obtain what we expect. See section below for details.

* '''Provide Graphics and Images.'''
Where possible obtain suitable graphics and images. Note all images, photos and graphics MUST be free for commercial use (please flag to us beforehand any items you are unsure about).

* '''Work with us.'''
Keep in contact and let us know if you are writing something specific, the content of the next issue is usually allocated quickly so it is helpful to know in advance the topic area and estimates of how long it will take you to produce the article.

Make sure you keep us updated if it is targeted for a specific issue. Often an early draft can help give us a headstart with graphics, layout, proofreading and feedback, so that the article is ready in time.

* '''Don't panic!'''
It is common not to know where to start when writing an article, my advice is to start with writing out what you aim to achieve in the article and why are you writing it (this may not end up in the final article, but it helps focus what you are doing).

* '''Ask for Help.'''
'''Out of Ideas?''' Working on the magazine, we all have 1000s of ideas for articles, but very little time to produce them, so if you want to write but not sure what about, then we can probably give you some ideas (simply let us know what topics you are interested in!).

'''Stuck on something?''' Chances are we may be able to help, or do some testing if required.

'''Need graphics?''' The team can help source and produce graphics if you are unable to obtain suitable ones.

'''Unsure about layouts?''' The article will go through the layout team before publishing, so have a go and if you aren't happy ensure we have enough time to let the layout team work on it.

* '''Enjoy it!'''
Try to pick something you are passionate about sharing with the world. It is an amazing feeling when you see your article published at the end of the month.

=== Setting Up Scribus ===
Using the latest Debian image, Scribus can be installed from terminal:
sudo apt-get install scribus

Authors should use the MagPi Scribus template (found on the [[TheMagPiLayout]] page).

=== Timescales & Deadlines ===
While we currently do not have a fixed deadline for articles it is worth remembering the stages we go through:

====Day 1-2 - The magazine content is agreed upon by the Team.====
Articles submitted or suggested after this point are likely to be put in following issues. Usually we have the outline of the content (and then order) worked out in the first few days of the month. We also review how the team got on in the previous month and what we can improve next month.

''Completion Action: Bare-bones version of the magazine is put on Issuu with article place-holders.''

====Week 1 - Prepare Articles====
Authors contacted to ensure articles will be ready. Work with authors to ensure content is in suitable format for use, including graphics and layout (please submit early if help is needed - do not under-estimate how long it takes to prepare graphics and layout).

''Completion Action: Everyone has a good idea of what they need to do and when.''

====Week 2 - Article Drafts Received, Layout & Testing Started====
We aim to start uploading completed/draft articles on to Issuu by this week. Additional work may be required with layout and graphics but full content is required. The status of the planned articles will be reviewed and replacements considered if content is not likely to be ready in time/testing shows issues.

''Completion Action: Draft articles should appear on the Issuu Live Draft''

====Week 3 - All Articles Posted For Proofreading====
By this stage we should have all the articles in the draft of the magazine live on Issuu.

''Completion Action: Completed articles should appear on the Issuu Live Draft''

====Week 4 - Final Proof and Checking====
All input from the authors should now be finished, any changes which impact layout etc probably won't be accepted.

''Completion Action: The Issuu Live Draft updated frequently with proof-reading feedback''

====Last Day of Month - Magazine is Completed====
The magazine is released either that night or the following day. Then we start all over!

''Completion Action: Release and look through what has been managed in a month!''

RPi Tutorial EGHS:LED output

2012-12-08T09:06:55Z

Meltwater: /* Circuit 2 - LED Driving Circuit (using Transistor Switching Circuit) */

{{Template:RPi Tutorials}}
==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==
The purpose of this guide is to enable control of an LED via the GPIO pins of the RPi.

This is the embedded version of writing a program to display "Hello World" and is the first step in getting started.

The first stage will be to build the hardware we are going to use, and then we shall look at the software which will drive it.

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

==The Hardware==
===Theory===
This is only a brief and rough overview, since the basics are covered in a lot more detail in many other places (see below).

The GPIO pins on the RPi when defined as an '''Output''' is able to cause the voltage on the pin to go '''HIGH (source)''' or '''LOW (sink)'''. This allows signals to be sent to other processors and devices like LEDs. However it is important to remember that the pin will only be able to Source or Sink very small currents, so higher powered devices (such as motors) can not be driven directly from a GPIO pin.

NOTE:
Depending on the specification of the RPi GPIO pins, the current SOURCE ability may be better,
than the SINK (or vice-a-versa).
i.e. If the RPi is able to SINK more current than it can SOURCE, then any driving circuit should
be between the RPi 3.3V pin and the GPIO pin (rather than GPIO pin and GND).

''For additional detail theory see'' <ref>[http://www.scriptoriumdesigns.com/embedded/gpio_out.php Introduction To Embedded Programming - GPIO Output]</ref>

===Circuit 1 - Basic LED Driving Circuit===
[[File:EGHS-LED_output1.jpg|100px|thumb|left|Basic LED Output Circuit 1]]
The resistor R1 is used to limit the current going through the LED (which has hardly any resistance), without the resistor, the LED will draw as much current as it can until it burns out (or burns out your GPIO pin).

The value you select for R1 will depend on the current required by the LED (upto 20mA depending on the LED used - check the datasheet) and the source current limit of the GPIO (launchpad is ~20mA), the RPi has a 50mA limit for the 3.3V supply line.

We also need to know the forward voltage required by the LED to light, typically around 2V-3.5V depending on colour<ref>[http://en.wikipedia.org/wiki/LED#Colors_and_materials Wikipedia:LED Forward Voltages]</ref>.

Finally, the output voltage of the RPi (and LaunchPad) GPIO is 3.3V output level.

Vout = 3.3V
Vled = 2V (I'm using RED)
Iled = 5mA = 0.005A

R1 = (Vout – Vled)/Iled
= (3.3 - 2)/0.005
= 260ohms (so 270ohms is closest preferred value)

If in doubt, use a bigger resistor (=less current & less brightness) and test if good enough by connecting across the 3.3V and ground pins (if you are just experimenting you are unlikely to need LEDs shining at their full brightness anyway).

For instance, one of my test circuits uses 470ohms (which only gives 2.7mA on 3.3V, but the same
circuit can be connected to a 12V supply without blowing the LED - rated @20mA).

====Basic LEDx8 Test Module====
Basic LEDx8 Test Module (Control pins at top, GND connection at bottom-right).
[[File:EGHS-LEDx8TestModule.jpg|200px|thumb|left|Basic LEDx8 Test Module]][[File:EGHS-LEDx8TestModuleDetailed.jpg|200px|thumb|centre|Circuit with track breaks marked in red]]

The above test module has been built to allow easy testing of GPIO outputs by driving up to 8 LEDs.
The resistor value 330 ohms is used (keeps the current draw fairly low).

===Circuit 2 - LED Driving Circuit (using Transistor Switching Circuit) ===
[[File:EGHS-LEDhigh output2.jpg|250px|thumb|left|Higher Power LED Driving Circuit]]

''For more detailed information about basic transistor circuits, some useful information is here<ref>[http://www.kpsec.freeuk.com/trancirc.htm The Electronics Club:Transistor Circuits].</ref>''

In order to drive a slightly higher current, the use of a transistor circuit will be required. Since all the driving current will be drawn through Vcc and through the transistor, the RPi 5volt line can be used for Vcc (this will limit the available current to 1Amp total draw from the USB supply itself - including the RPi draw). The current limit will be the nominal current the transistor can handle.

Note: Vcc = 5V in this example, but the 3V3 supply can be used too,
although remember that the 3V3 should be not used to supply over
120mA in total.

====Transistor Selection====
This circuit requires an NPN transistor. This circuit is not suitable for other types of transistor (example PNP, FET).

There is a huge range of transistors available, so I will pick a common & cheap one ([http://uk.farnell.com/fairchild-semiconductor/bc548/transistor-npn-to-92/dp/1467872 BC548] or [http://uk.farnell.com/multicomp/bc108/transistor-npn-to-18/dp/9206736 BC108]) and see how well it suits.

''More details on specific transistors see <ref>[http://www.kpsec.freeuk.com/components/tran.htm The Electronics Club:Transistor]</ref>''

The key characteristics of interest are:

maximum collector current Ic(max) : 100mA [BC548], 200mA [BC108]

minimum current gain hFE(min) : 110

Suggested hFE:
hFE(min) > 5 x (Iload/Iinput)
We assume we want to draw a very low current from the RPi GPIO,
so even with an hFE=110 and drawing only 5mA we can drive 110mA
(over BC548's Ic(max) limit anyway).

The current transistor I have available at the moment is ([http://uk.farnell.com/diodes-inc/ztx653/transistor-npn-e-line/dp/9525580 ZTX 653]):

maximum collector current Ic(max) : 2A

minimum current gain hFE(min) : 100

The use of a transistor allows the bulk of the driving current to pass through the transistor to ground, with only a small switching current required to be driven from the GPIO pin. For low powered driving circuits, most transistors will be suitable.

Transistors do have a limited amount of current handling ability, which can be improved by coupling together as a [http://www.kpsec.freeuk.com/components/tran.htm#darlington Darlington pair] (often available in a single package). Also higher powered switches such as mosfets, and even relays can be driven for higher power requirements.

====Calculating R1 - LED Current Limiting Resistor====
The value of R1 is similar to before, but since the driving voltage is higher, the same resister will allow more current, thus the LED will be brighter (unless we use a larger resistor).

When the transistor is on the voltage drop is minimal VCE(sat)(90-200mV), so we will just consider the LED voltage drop.

Vcc = 5V
Vled = 2V (I'm using RED)
Iled = 5mA = 0.005A
R1 = (Vcc – Vled)/Iled
= (5 - 2)/0.005
= 600ohms (so 560ohm or 680ohm will probably be fine)

====Calculating R2 - Transistor Base Resistor====
The value of R2 can be determined, as follows:

There seems to be two possible ways to approach this, one is to work out your required driving current through the collector (Ic) i.e. the driving current of the LED, and the other is to determine it's value from the recommended source current of the GPIO pin (for the RPi, 5mA or less is recommended).

The latter makes most sense to me, but will try both and see how they compare.

=====R2max - Based on driving current requirement (Ic)=====
Vc = 3.3V
hFE = 110
Ic = 100mA = 0.1A (may as well aim for full load)
R2 = (Vc x hFE) / (5 x Ic)
= (3.3 x 110) / (5 x 0.1)
= 726ohms
Although, since we don't need 100mA this resistor can probably be far larger.

=====R2min - Based on the GPIO pin source current=====
To fully switch on the transistor, most transistors require (Vbe) Base Emitter Turn-On Voltage to be around 700mV on the base (it depends slightly on the type, see it's data sheet).

Vgpio = 3.3V
Iout = 5mA = 0.005
Vbe Base Emitter Turn-On Voltage = 0.7V
R2 = (Vgpio - Vbe) / Iout
= (3.3 - 0.7) / (0.005)
= 520ohms (so 560ohm nearest value)
(For reference, if a Darlington pair was used,
Vbe would be 1.4V (effectively driving two
transistors, so R2 would be 380ohms)).

====Testing====
We can test our calculated values by using a simple prototype circuit, and compare an LED driven directly and through the ([http://uk.farnell.com/diodes-inc/ztx653/transistor-npn-e-line/dp/9525580 ZTX 653]) transistor.

In the following circuit, Vcc = 5V (main supply voltage - red wires) and Vgpio = 3.3V (representing the GPIO output - bottom blue wire) is connected to the transistor base through R2 (560ohm) resistor.
[[File:EGHS-LEDTransTest.jpg|100px|thumb|left|LED Transistor Circuit Test]]

There is very little difference between the LED brightness*, and even when the transistor base is connected directly to 3.3V (Vgpio) there is no change(indicating that the transistor is saturated i.e. fully turned on).

*Note, there is slight difference due to the current drawn by the transistor itself.
Also, the LED test circuit is used from before, rather than the calculated R1.

I suggest by using a combination of these two calculations you will obtain, a max value (R2max - Based on driving current requirement (Ic)) and a min value (R2min - Based on the GPIO pin source current) for R2.

Generally the larger the R2 is the less current will be drawn from the GPIO pin, however less current will be available through the transistor for the load (Ic) if R2 is too large.

==The Software==
While the RPi is not available, I can only confirm the TI LaunchPad code works for me.
===TI LaunchPad===

Sample test code for Basic LEDx8 Test Module (tested on TI MSP430G2553 device).

Basic LEDx8 Test Module input pins 0-7 wired to device Port1:0 to Port1:7, plus GND connection.

Code:
* [http://www.pastebucket.com/1455 hwmap_ledx8module.h] - Hardware Mapping File (LED0 to LED7 mapped to GPIO Port1:0 to Port1:7)

* [http://www.pastebucket.com/1452 main.c] - Main calling functions

* [http://www.pastebucket.com/1453 ledx8module.c] - Sample routines

* [http://www.pastebucket.com/1454 ledx8module.h] - Mapping LED types etc

===RPi===
The above circuits ''should'' work with code similar to that given in ''([[RPi Low-level peripherals#Code examples]])'' section.

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Tutorial EGHS:LED output

2012-12-08T09:06:30Z

Meltwater: /* Circuit 2 - LED Driving Circuit (using Transistor Switching Circuit) */

{{Template:RPi Tutorials}}
==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==
The purpose of this guide is to enable control of an LED via the GPIO pins of the RPi.

This is the embedded version of writing a program to display "Hello World" and is the first step in getting started.

The first stage will be to build the hardware we are going to use, and then we shall look at the software which will drive it.

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

==The Hardware==
===Theory===
This is only a brief and rough overview, since the basics are covered in a lot more detail in many other places (see below).

The GPIO pins on the RPi when defined as an '''Output''' is able to cause the voltage on the pin to go '''HIGH (source)''' or '''LOW (sink)'''. This allows signals to be sent to other processors and devices like LEDs. However it is important to remember that the pin will only be able to Source or Sink very small currents, so higher powered devices (such as motors) can not be driven directly from a GPIO pin.

NOTE:
Depending on the specification of the RPi GPIO pins, the current SOURCE ability may be better,
than the SINK (or vice-a-versa).
i.e. If the RPi is able to SINK more current than it can SOURCE, then any driving circuit should
be between the RPi 3.3V pin and the GPIO pin (rather than GPIO pin and GND).

''For additional detail theory see'' <ref>[http://www.scriptoriumdesigns.com/embedded/gpio_out.php Introduction To Embedded Programming - GPIO Output]</ref>

===Circuit 1 - Basic LED Driving Circuit===
[[File:EGHS-LED_output1.jpg|100px|thumb|left|Basic LED Output Circuit 1]]
The resistor R1 is used to limit the current going through the LED (which has hardly any resistance), without the resistor, the LED will draw as much current as it can until it burns out (or burns out your GPIO pin).

The value you select for R1 will depend on the current required by the LED (upto 20mA depending on the LED used - check the datasheet) and the source current limit of the GPIO (launchpad is ~20mA), the RPi has a 50mA limit for the 3.3V supply line.

We also need to know the forward voltage required by the LED to light, typically around 2V-3.5V depending on colour<ref>[http://en.wikipedia.org/wiki/LED#Colors_and_materials Wikipedia:LED Forward Voltages]</ref>.

Finally, the output voltage of the RPi (and LaunchPad) GPIO is 3.3V output level.

Vout = 3.3V
Vled = 2V (I'm using RED)
Iled = 5mA = 0.005A

R1 = (Vout – Vled)/Iled
= (3.3 - 2)/0.005
= 260ohms (so 270ohms is closest preferred value)

If in doubt, use a bigger resistor (=less current & less brightness) and test if good enough by connecting across the 3.3V and ground pins (if you are just experimenting you are unlikely to need LEDs shining at their full brightness anyway).

For instance, one of my test circuits uses 470ohms (which only gives 2.7mA on 3.3V, but the same
circuit can be connected to a 12V supply without blowing the LED - rated @20mA).

====Basic LEDx8 Test Module====
Basic LEDx8 Test Module (Control pins at top, GND connection at bottom-right).
[[File:EGHS-LEDx8TestModule.jpg|200px|thumb|left|Basic LEDx8 Test Module]][[File:EGHS-LEDx8TestModuleDetailed.jpg|200px|thumb|centre|Circuit with track breaks marked in red]]

The above test module has been built to allow easy testing of GPIO outputs by driving up to 8 LEDs.
The resistor value 330 ohms is used (keeps the current draw fairly low).

===Circuit 2 - LED Driving Circuit (using Transistor Switching Circuit) ===
[[File:EGHS-LEDhigh output2.jpg|250px|thumb|left|Higher Power LED Driving Circuit]]

''For more detailed information about basic transistor circuits, some useful information is here<ref>[http://www.kpsec.freeuk.com/trancirc.htm The Electronics Club:Transistor Circuits].</ref>''

In order to drive a slightly higher current, the use of a transistor circuit will be required. Since all the driving current will be drawn through Vcc and through the transistor, the RPi 5volt line can be used for Vcc (this will limit the available current to 1Amp total draw from the USB supply itself - including the RPi draw). The current limit will be the nominal current the transistor can handle.

Note: Vcc = 5V in this example, but the 3V3 supply can be used too, although remember that the 3V3 should be not used to supply over 120mA.

====Transistor Selection====
This circuit requires an NPN transistor. This circuit is not suitable for other types of transistor (example PNP, FET).

There is a huge range of transistors available, so I will pick a common & cheap one ([http://uk.farnell.com/fairchild-semiconductor/bc548/transistor-npn-to-92/dp/1467872 BC548] or [http://uk.farnell.com/multicomp/bc108/transistor-npn-to-18/dp/9206736 BC108]) and see how well it suits.

''More details on specific transistors see <ref>[http://www.kpsec.freeuk.com/components/tran.htm The Electronics Club:Transistor]</ref>''

The key characteristics of interest are:

maximum collector current Ic(max) : 100mA [BC548], 200mA [BC108]

minimum current gain hFE(min) : 110

Suggested hFE:
hFE(min) > 5 x (Iload/Iinput)
We assume we want to draw a very low current from the RPi GPIO,
so even with an hFE=110 and drawing only 5mA we can drive 110mA
(over BC548's Ic(max) limit anyway).

The current transistor I have available at the moment is ([http://uk.farnell.com/diodes-inc/ztx653/transistor-npn-e-line/dp/9525580 ZTX 653]):

maximum collector current Ic(max) : 2A

minimum current gain hFE(min) : 100

The use of a transistor allows the bulk of the driving current to pass through the transistor to ground, with only a small switching current required to be driven from the GPIO pin. For low powered driving circuits, most transistors will be suitable.

Transistors do have a limited amount of current handling ability, which can be improved by coupling together as a [http://www.kpsec.freeuk.com/components/tran.htm#darlington Darlington pair] (often available in a single package). Also higher powered switches such as mosfets, and even relays can be driven for higher power requirements.

====Calculating R1 - LED Current Limiting Resistor====
The value of R1 is similar to before, but since the driving voltage is higher, the same resister will allow more current, thus the LED will be brighter (unless we use a larger resistor).

When the transistor is on the voltage drop is minimal VCE(sat)(90-200mV), so we will just consider the LED voltage drop.

Vcc = 5V
Vled = 2V (I'm using RED)
Iled = 5mA = 0.005A
R1 = (Vcc – Vled)/Iled
= (5 - 2)/0.005
= 600ohms (so 560ohm or 680ohm will probably be fine)

====Calculating R2 - Transistor Base Resistor====
The value of R2 can be determined, as follows:

There seems to be two possible ways to approach this, one is to work out your required driving current through the collector (Ic) i.e. the driving current of the LED, and the other is to determine it's value from the recommended source current of the GPIO pin (for the RPi, 5mA or less is recommended).

The latter makes most sense to me, but will try both and see how they compare.

=====R2max - Based on driving current requirement (Ic)=====
Vc = 3.3V
hFE = 110
Ic = 100mA = 0.1A (may as well aim for full load)
R2 = (Vc x hFE) / (5 x Ic)
= (3.3 x 110) / (5 x 0.1)
= 726ohms
Although, since we don't need 100mA this resistor can probably be far larger.

=====R2min - Based on the GPIO pin source current=====
To fully switch on the transistor, most transistors require (Vbe) Base Emitter Turn-On Voltage to be around 700mV on the base (it depends slightly on the type, see it's data sheet).

Vgpio = 3.3V
Iout = 5mA = 0.005
Vbe Base Emitter Turn-On Voltage = 0.7V
R2 = (Vgpio - Vbe) / Iout
= (3.3 - 0.7) / (0.005)
= 520ohms (so 560ohm nearest value)
(For reference, if a Darlington pair was used,
Vbe would be 1.4V (effectively driving two
transistors, so R2 would be 380ohms)).

====Testing====
We can test our calculated values by using a simple prototype circuit, and compare an LED driven directly and through the ([http://uk.farnell.com/diodes-inc/ztx653/transistor-npn-e-line/dp/9525580 ZTX 653]) transistor.

In the following circuit, Vcc = 5V (main supply voltage - red wires) and Vgpio = 3.3V (representing the GPIO output - bottom blue wire) is connected to the transistor base through R2 (560ohm) resistor.
[[File:EGHS-LEDTransTest.jpg|100px|thumb|left|LED Transistor Circuit Test]]

There is very little difference between the LED brightness*, and even when the transistor base is connected directly to 3.3V (Vgpio) there is no change(indicating that the transistor is saturated i.e. fully turned on).

*Note, there is slight difference due to the current drawn by the transistor itself.
Also, the LED test circuit is used from before, rather than the calculated R1.

I suggest by using a combination of these two calculations you will obtain, a max value (R2max - Based on driving current requirement (Ic)) and a min value (R2min - Based on the GPIO pin source current) for R2.

Generally the larger the R2 is the less current will be drawn from the GPIO pin, however less current will be available through the transistor for the load (Ic) if R2 is too large.

==The Software==
While the RPi is not available, I can only confirm the TI LaunchPad code works for me.
===TI LaunchPad===

Sample test code for Basic LEDx8 Test Module (tested on TI MSP430G2553 device).

Basic LEDx8 Test Module input pins 0-7 wired to device Port1:0 to Port1:7, plus GND connection.

Code:
* [http://www.pastebucket.com/1455 hwmap_ledx8module.h] - Hardware Mapping File (LED0 to LED7 mapped to GPIO Port1:0 to Port1:7)

* [http://www.pastebucket.com/1452 main.c] - Main calling functions

* [http://www.pastebucket.com/1453 ledx8module.c] - Sample routines

* [http://www.pastebucket.com/1454 ledx8module.h] - Mapping LED types etc

===RPi===
The above circuits ''should'' work with code similar to that given in ''([[RPi Low-level peripherals#Code examples]])'' section.

==References==
<references/>

{{Template:Raspberry Pi}}

TheMagPiLayout

2012-12-05T09:03:37Z

Meltwater:

[[File:TheMagPi.png|right|link=http://www.themagpi.com]]

== Software ==

Since Raspbian (Debian 7/Wheezy) is used for layout, the version of Scribus with this LINUX distribution is used for all layouts. This corresponds to Scribus 1.4.1.svn. To install this version of Scribus type,

<tt>
sudo apt-get install scribus
</tt>

on a Raspbian installation.

== Scribus Page Layout Template ==
MagPi Scribus Template V2 (zip) : [[File:2-page-template-for-wheezy-by-jaseman-V2.zip]]

== Page margins ==
=== Outer margins ===
* The paper size is A4.
* The units are set to millimetres.
* The outer margins are:
** top 10mm
** bottom 10mm
** non-spine 10mm
** spine 20mm

== Fonts ==

If the document is converted with a non-LINUX version of Scribus, the FreeSans font set is typically not available. This results in PDF files which contain the wrong fonts.

=== Title fonts ===

The title font should be taken from one of those present in the standard version of Scribus.

=== Section headings ===

Section headings should be FreeSans Bold 14Pt and underlined.

=== Body text ===

Normal text within the body of an article should be FreeSans Regular 12pt.

=== Fixed width text ===

Programming code or instructions that must be typed in as part of a tutorial should be Courier 10 Pitch Regular font 10pt. In some instances, (C or C++ code) Courier is too wide to prevent multiple line wraps. In these cases, Monaco 10pt can be used instead of Courier. Articles of a given type should preserve this choice from the first instance onwards.

=== Author ===

The author should be quoted at the end of the article as,

<code>Article by John Doe</code>

The font should be FreeSans Bold Oblique 14pt.

=== Page numbers ===

The page numbers should be black FreeSans Bold Oblique 16pt.

== Article title ==

The article title area is 180mm wide and 30mm deep.

== Two column layout ==

File:2-page-template-for-wheezy-by-jaseman-V2.zip

2012-12-05T09:00:10Z

Meltwater: Meltwater uploaded a new version of "File:2-page-template-for-wheezy-by-jaseman-V2.zip": MagPi Scribus Template for Authors

MagPi Scribus Template For Authors

File:2-page-template-for-wheezy-by-jaseman-V2.zip

2012-12-05T08:59:26Z

Meltwater: MagPi Scribus Template For Authors

MagPi Scribus Template For Authors

TheMagPi

2012-12-03T13:47:34Z

Meltwater:

[[File:TheMagPi.png|right|link=http://www.themagpi.com]]

== Overview ==

[http://www.themagpi.com/ The Mag Pi] magazine is written by the Raspberry Pi community for the community. The authors, layout team and editor come from teaching, IT industry and other professions. The aim of the magazine is given in detail on [http://www.themagpi.com/mission_statement/ the Mag Pi web site].

== Obtaining a copy ==

The magazine is available in [http://www.themagpi.com/ electronic formats] (pdf and flash) as well as a [https://www.modmypi.com/shop/the-magpi-magazine printed magazine]. Since this is a community project, it is helpful to donate a small amount or purchase one printed copy of the magazine. Proceeds from sales and donations go towards the community and keeping the magazine online.

Our kickstarter project was launched on 1st December 2012 to allow us to print a collectors edition of the 8 Issues we produced in 2012 (details here: [http://www.kickstarter.com/projects/themagpi/the-magpi-magazine-from-virtual-to-reality The MagPi Magazine - From Virtual to Reality]).

== Helping with the magazine ==
There are several ways you can get involved with the magazine, depending on the time and skills you have available.

=== Donating Money ===
An obvious way to help the magazine is to donate towards the running costs of the magazine. There are lots of costs involved with running the site and maintaining the magazine and additional funds will allow us to expand the project to reach more readers.

A paypal donate button is on the main page of the [[http://www.themagpi.com/ MagPi site]].

=== Submit an Article ===
We encourage people to submit their articles to us, simply email the editor (details on the [[http://www.themagpi.com/ MagPi site]]), with your idea or article and we shall discuss if and when we can fit it in.

Articles can be about anything to do with the Raspberry Pi and it's use.

Please read through the [[RPi_MagPi_InfoForAuthors | Information for Authors]] page for details.

=== Design or layout contributions ===

The editor is on the lookout for additional design and layout assistance. Those interested in helping should contact the editor (editor@themagpi.com).

=== Proof reading ===

Each article is prepared as an [http://issuu.com/themagpi issuu draft] before it is finalised. This allows the community to view and discuss the articles as they are being developed.

The editor welcomes comments on the content, spelling or grammar during the preparation process.

=== Join the team ===

Obviously the best way to help with the MagPi is to donate your time and skills by joining the team. Email the editor if you are interested.

At present we communicate using a GoogleGroup to work on and discuss the production of each issue, we always welcome new members to get involved.

TheMagPi

2012-12-03T12:55:29Z

Meltwater: /* Obtaining a copy */

[[File:TheMagPi.png|right|link=http://www.themagpi.com]]

== Overview ==

[http://www.themagpi.com/ The Mag Pi] magazine is written by the Raspberry Pi community for the community. The authors, layout team and editor come from teaching, IT industry and other professions. The aim of the magazine is given in detail on [http://www.themagpi.com/mission_statement/ the Mag Pi web site].

== Obtaining a copy ==

The magazine is available in [http://www.themagpi.com/ electronic formats] (pdf and flash) as well as a [https://www.modmypi.com/shop/the-magpi-magazine printed magazine]. Since this is a community project, it is helpful to donate a small amount or purchase one printed copy of the magazine. Proceeds from sales and donations go towards the community and keeping the magazine online.

Our kickstarter project was launched on 1st December 2012 to allow us to print a collectors edition of the 8 Issues we produced in 2012 (details here: [http://www.kickstarter.com/projects/themagpi/the-magpi-magazine-from-virtual-to-reality The MagPi Magazine - From Virtual to Reality]).

== Helping with the magazine ==
There are several ways you can get involved with the magazine, depending on the time and skills you have available.

=== Donating Money ===
An obvious way to help the magazine is to donate towards the running costs of the magazine. There are lots of costs involved with running the site and maintaining the magazine and additional funds will allow us to expand the project to reach more readers.

A paypal donate button is on the main page of the [[http://www.themagpi.com/ MagPi site]].

=== Submit an Article ===
We encourage people to submit their articles to us, simply email the editor (details on the [[http://www.themagpi.com/ MagPi site]]), with your idea or article and we shall discuss if and when we can fit it in.

Articles can be about anything to do with the Raspberry Pi and it's use.

Please read through the [[RPi_MagPi_InfoForAuthors | Information for Authors]] page for details.

== Design or layout contributions ==

The editor is on the lookout for additional design and layout assistance. Those interested in helping should contact the editor (editor@themagpi.com).

== Proof reading ==

Each article is prepared as an [http://issuu.com/themagpi issuu draft] before it is finalised. This allows the community to view and discuss the articles as they are being developed.

The editor welcomes comments on the content, spelling or grammar during the preparation process.

== Join the team ==

Obviously the best way to help with the MagPi is to donate your time and skills by joining the team. Email the editor if you are interested.

At present we communicate using a GoogleGroup to work on and discuss the production of each issue, we always welcome new members to get involved.

TheMagPi

2012-12-03T12:52:04Z

Meltwater: added more author info.

[[File:TheMagPi.png|right|link=http://www.themagpi.com]]

== Overview ==

[http://www.themagpi.com/ The Mag Pi] magazine is written by the Raspberry Pi community for the community. The authors, layout team and editor come from teaching, IT industry and other professions. The aim of the magazine is given in detail on [http://www.themagpi.com/mission_statement/ the Mag Pi web site].

== Obtaining a copy ==

The magazine is available in [http://www.themagpi.com/ electronic formats] (pdf and flash) as well as a [https://www.modmypi.com/shop/the-magpi-magazine printed magazine]. Since this is a community project, it is helpful to donate a small amount or purchase one printed copy of the magazine. Proceeds from sales and donations go towards the community and keeping the magazine online.

== Helping with the magazine ==
There are several ways you can get involved with the magazine, depending on the time and skills you have available.

=== Donating Money ===
An obvious way to help the magazine is to donate towards the running costs of the magazine. There are lots of costs involved with running the site and maintaining the magazine and additional funds will allow us to expand the project to reach more readers.

A paypal donate button is on the main page of the [[http://www.themagpi.com/ MagPi site]].

=== Submit an Article ===
We encourage people to submit their articles to us, simply email the editor (details on the [[http://www.themagpi.com/ MagPi site]]), with your idea or article and we shall discuss if and when we can fit it in.

Articles can be about anything to do with the Raspberry Pi and it's use.

Please read through the [[RPi_MagPi_InfoForAuthors | Information for Authors]] page for details.

== Design or layout contributions ==

The editor is on the lookout for additional design and layout assistance. Those interested in helping should contact the editor (editor@themagpi.com).

== Proof reading ==

Each article is prepared as an [http://issuu.com/themagpi issuu draft] before it is finalised. This allows the community to view and discuss the articles as they are being developed.

The editor welcomes comments on the content, spelling or grammar during the preparation process.

== Join the team ==

Obviously the best way to help with the MagPi is to donate your time and skills by joining the team. Email the editor if you are interested.

At present we communicate using a GoogleGroup to work on and discuss the production of each issue, we always welcome new members to get involved.

RPi MagPi InfoForAuthors

2012-12-03T12:43:41Z

Meltwater: Created info for authors page

RPi Documentation

2012-11-19T09:11:59Z

Meltwater: /* Schematics */ - Added Rev 2.0

{{Template:RPi Resources}}

Note: All datasheets, documents and Trademarks remain the property of their respective owners.

=Published Datasheets=
==User Guides==
[http://www.amazon.com/Raspberry-User-Guide-Gareth-Halfacree/dp/111846446X/ref=sr_1_2?ie=UTF8&qid=1347122064&sr=8-2&keywords=raspberry+pi Raspberry Pi Users Guide eBook now available at Amazon]

[http://elinux.org/File:Raspi-Model-AB-Mono-2-699x1024.png Raspberry Pi Model A/Model B Layout Diagram]

==Hardware / Software Datasheets==
===Raspberry Pi Processor Broadcom System-On-Chip:===
[http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf BCM2835 ARM Peripherals] - ([[BCM2835 datasheet errata]])

[http://www.scribd.com/doc/101830961/GPIO-Pads-Control2 GPIO Datasheet Addendum - GPIO Pads Control]

===ARM 11 CPU Core:===
[http://infocenter.arm.com/help/topic/com.arm.doc.ddi0301h/DDI0301H_arm1176jzfs_r0p7_trm.pdf (ARM1176JZF-S)]

===Model B LAN Chip:===
[http://www.smsc.com/media/Downloads_Public/Data_Briefs/9512db.pdf (LAN9512) Data Brief] | [http://www.smsc.com/media/Downloads_Public/Data_Sheets/9512.pdf (LAN9512) Datasheet])

==Mechanical Data==
===Production Boards (2012 Q1):===
none available yet
===Beta Boards:===
[http://www.scribd.com/doc/77785093/Raspberry-Pi-initial-Beta-boards-Mechanical Gert's Beta Boards Mechanical Data]

==Schematics==
===Production Boards ===
==== Rev 2.0 (2012 Q3):====
PCB includes mounting holes, and additional P5 GPIO Header (256Mb RAM briefly - 512Mb typical)

[http://www.raspberrypi.org/wp-content/uploads/2012/10/Raspberry-Pi-R2.0-Schematics-Issue2.2_027.pdf Raspberry Pi Rev 2.0 Electrical Schematics]

==== Rev 1.0 (2012 Q1):====
Does not include mounting holes or P5 header (256Mb RAM Only).

[http://www.raspberrypi.org/wp-content/uploads/2012/04/Raspberry-Pi-Schematics-R1.0.pdf Raspberry Pi Rev 1.0 Electrical Schematics]

===Beta Boards:===
[http://www.raspberrypi.org/wp-content/uploads/2011/11/gerbers2.png Beta Board PCB Layers Screenshot]

[http://lh3.googleusercontent.com/-uO4l8pwSLvU/TsQGbth6x6I/AAAAAAAAAkk/5zQMH3uKPiE/s829/Boardlayout.png Beta Board PCB Layers Screenshot, labelled version]

=Additional Published Information=
==Gert Board:==
[http://www.scribd.com/doc/88286916/Gertboard-Overview Gertboard-Overview]

[http://www.element14.com/community/servlet/JiveServlet/downloadBody/48860-102-3-256002/Gertboard_User_Manual_Rev_1%200_F.pdf Gertboard Users Manual (pdf)]

[http://www.element14.com/community/servlet/JiveServlet/downloadBody/48916-102-1-256003/Gertboard_Assembly_Manual_Rev1.1_F.pdf Gertboard Assembly Manual (pdf)]

==Power Supply Details:==
[http://www.scribd.com/doc/69700160/Rasp-Why-Does-It-Use-More-Power Detailed explanation of the Beta board power supply]

[http://www.raspberrypi.org/wp-content/uploads/2011/12/psu.png Preliminary power supply schematic, Beta board]

=Documentation Projects=
==Low Level Documentation==
This section lists community produced documentation of low level aspects of the Raspberry Pi that are not documented elsewhere.

* [[RPi Framebuffer]] - Documentation on BCM2835's frame buffer and mailbox. Also documented in more detail [https://github.com/raspberrypi/firmware/wiki here]
* [[RPI vcgencmd usage]] - Documentation for the vcgencmd command.

==Frambozenier.org Datasheets:==
[[RPi DatasheetCategories | Frambozenier.org Documentation Project Datasheets]] - Selection of detailed datasheets on the Raspberry Pi (developed on the wiki, reviewed then published).

{{Template:Raspberry Pi}}

RPi raspi-config

2012-09-14T09:57:57Z

Meltwater: Added some structure to the document

This article applies to the Wheezy Raspbian official release of 15/7/2012.

raspi-config was introduced with the advent of the Debian Wheezy image. It helps you configure your Pi. It is a work in progress so the number of menu items and the ease of use of those items will increase with time. If anyone feels willing and able to improve raspi-config then please contact Alex Bradbury [https://github.com/asb/raspi-config].

== The raspi-config ==

When you start your Pi for the first time using the Wheezy image then, following lots of scrolling text with a couple of pauses lasting in total a few tens of seconds, the raspi-config menu will appear. It has the following entries:

info Information about this tool
expand-rootfs Expand root partition to fill SD card
overscan Change overscan
configure-keyboard Set keyboard layout
change_pass Change password for ‘pi’ user
change_locale Set locale
change_timezone Set timezone
memory_split Change memory split
ssh Enable or disable ssh server
boot_behaviour Start desktop on boot?
update Try to upgrade raspi-config
<Select> <Finish>

== Moving Around the Menu ==

At any point from within any of the menu or sub-menu options the Tab key will toggle about the selected entry and the options at the bottom inside angle brackets, cursor keys move up and down menus. There is an exception to this and that’s with the change_locale option, ignore that exception for now it’s covered later.

Some of the menu entries take quite a while to display. The user experience looks like its running a desktop but in fact it isn't; its using the command line and its graphics capabilities (remember VDU's?) so occasionally the screen will scroll a bit.

== What raspi-config does ==

Some menu entries modify the file /boot/config.txt. This file, out of the box, contains a number of commented out configuration entries; raspi-config adds entries at the end of this file. You can see what raspi-config has done to the file by viewing it on the Pi using Leafpad and, if you really mess things up you can edit the file from the SD card using Notepad on a Windows PC. More information on editing config.txt here [[R-Pi_ConfigurationFile]]

Other entries modify Linux configuration files, some take effect immediately, others at the next boot.

== INFO - Information About This Tool ==

This would be really helpful if it actually explained the options in the menu, hopefully at least it will provide a reference to this Wiki page.

It helpfully advises you may have difficulties if you have heavily customized your installation but as this is probably the first thing a rookie is going to see the likelihood of a heavily customized installation is small.

== Running raspi-config another time ==
Following the first boot, your raspberry pi will boot into the command prompt or desktop (depending on your choice).

You can run it at any time after that by typing (case sensitive):
sudo raspi-config
At the command line or in a terminal window. The sudo (do as superuser) is necessary because you will be changing files that you as user pi do not own, its Debian's way of providing a root login.

The lovely thing about the Pi is that, if you mess up, it will not be difficult to re-image.

== Menu Options ==
=== EXPAND-ROOTFS - Expand Root Partition to Fill SD Card ===

This does what it says on the tin so if you have installed Wheezy on a 4GB or greater card use this option and AFTER REBOOT it will use all of the SD card. The Wheezy image takes nearly 2GB so if you are going to install additional software or large files its worth doing, however you don't need to do it on first boot. The downside of using all of a larger card is that it takes much longer to backup the image.

=== OVERSCAN - Change Overscan ===

What would you like to do with overscan
<Disable> <Enable>

Any changes will take effect after a reboot. If you change a setting and end up losing the left side of the screen you can easily edit /boot/config.txt on a PC to undo the changes.

Televisions do not usually display the whole of the picture, they Overscan and crop off a few percent of the image. This is to hide the data signals such as teletext which use the outer lines of the picture (could be a hangover from analogue TV). Computers, including the Pi, use all the lines for real display so often the image displayed by computers on TV's is cropped.

To avoid losing the critical left column at first boot the clever Pi people have deliberately enabled Overscan and used positive Overscan vlauses to make the displayed image smaller, and to play safe much smaller. This means, depending on your monitor/TV, there may be black borders around the picture. LXDE will show the wrong resolution in its display information as it shows you the size of the framebuffer (display_size - overscan).

On some displays, particularly monitors, just disabling Overscan will make the picture fill the whole screen and correct the resolution. For other displays it may be necessary to leave overscan enabled and fiddle with Overscan values, more information here [[R-Pi_Troubleshooting#Big_black_borders_around_small_image_on_HD_monitors]].

=== CONFIGURE-KEYBOARD - Set keyboard layout ===

Slow to display and, if you select some of the non-default options, there will be a short delay while changes are made. Changes take effect immediately except for changes to X-server exit which require a reboot.

This menu for using different attached keyboards. Brands of keyboards are chosen first followed by other choices to set up nationality of keyboards etc.

Default is Generic 105-key (Intl) PC. If you cannot find your keyboard on the list then use one of the generic keyboards but it’s probably not a big deal if you can't find yours on the list, have fun remember you can always, change it later or re-image if you're really stuck.

The next screen regards keyboard layout. If you are not using the first choice of English UK select Other and you will be faced with a long list of other national keyboards. Funnily enough this list includes English UK.

Next screen is quite well documented on the screen you're probably going to run with one of the top two choices. These are:

The default for the keyboard layout
Or
No AltGr key

To be honest if this is your first setup and you get this wrong it’s not going to break the bank and as I keep saying if in doubt re-image and start again.

Next screen; well if your using a standard keyboard then you probably don’t have a compose key and if your new to computing as intended you're not likely to need one for a while so I would suggest choosing

No compose key

The next screen is a useful one and the on screen documentation is actually quite clear provided you know what is meant by “X server” so here’s an outline:

If you choose to boot to the command line (see later) then after login the Pi will tell you that you can run startx. Startx is the command to run the windows (like) screen where you use a mouse to select options.

This is the X server and to get back to command line (that’s all the typed stuff) you can use [Ctrl][Alt][Backspace] all pressed at the same time to shut down this X server screen; you can always restart it by typing “startx”. Always handy if you have a flaky mouse or are using a wireless mouse that eats batteries.

Of course this is pointless if you don’t remember the key combination when the time comes!

=== CHANGE_PASS - Change password for ‘pi’ user ===

The default user for the Wheezy install is pi and its password is raspberry. Until you're familiar with the setup it’s probably better to leave this password as it is at least till you are happy changing stuff. In addition you can re-run raspi-config to change it at any time.

If you screw this up be prepared to re-image and lose any work you have done and programs installed (you did back up your data didn't you). With Linux and Unix forgotten passwords are a killer the Raspberry Pi is one of the simpler systems. Let's face it till you know what your looking at, the out of the box solution of pi and raspberry are probably all you will need.

=== CHANGE_LOCALE - Set locale ===

Slow to start up and there will be a delay while locales are generated.

You can tell this was written by a computer engineer and not a human how about this as an alternative.

change_locale Tell the computer if you need non English characters.

Sheesh! a computer aimed at children and new users and then you expect them to know what locale means (Google's your friend?).

This menu option gives you a massive list of choices that look like they were written by one of the infinite monkeys of legend (goggle infinite monkeys Shakespeare if you don’t understand this reference).

The default setting is

en_GB UTF-8 UTF-8 (ain't it nice to have a UK produced computer!)

English, Great Britain and UTF-8 is a code related to showing all of the characters usually needed to show English letters and other symbols on the screen. If you are working in some other language than English then you will probably need to play around with this.

You can select multiple choices in the list the space bar toggles them on and off (this was the exception I mentioned earlier) and it’s a long list. Basically if you want to work in more than one language then you will need to make other choices from this list based on the languages you intend to use.

If you are working in English only the default choice is probably the only one you will need.

=== CHANGE_TIMEZONE - Set timezone ===

Slow to display.

This is where you setup your clock; now it’s no big issue if it’s wrong it just means the date and time assigned to files you create (automatically when you make them) will be out and its not hard to set this up. (What is the effect if you are not connected to the internet and don't have time set with ntp?)

The set up consists of two layers basically to make your selection easier to find.

First option screen think Continent; just to confuse things you have US and America because we all know USA is not part of America. Actually the US option just gives you a shorter list containing the US time zones that are included in the American list; they just made a shorter list under US for all those Good Old Boy American Citizens who don’t know about American places outside of the USA. (flames imminent!).

SystemV relies on you knowing what SystemV is (Think Unix and ignore it for now).

Most people know where they are in the world for time zone; for me it’s Europe then London on the next screen but I’ve always been of the opinion that there should be ropes and lights around the M25 with signs saying “Danger hole in the world Keep Out” but then I’m not from London and the M25 was always the road to hell.

=== MEMORY_SPLIT - Change memory split ===

This allows you to choose how much of the RAM memory is set aside for the Broadcom Graphics Processing Unit (Videocore) and how much for the operation of the main ARM processor.

Three choices 32MiB for Videocore, 64MiB for Videocore, 128MiB for Videocore. First time users should leave it at the default 64MiB for the Videocore. There is more information on when to use the different options here [[RPi_Advanced_Setup]]. You can change it with raspi-config and it will take effect at the next reboot (check).

Now let’s assume your really fresh to writing code, as in never done this before ever. You're not going to be writing really complex Artificial Intelligence type programs and your also unlikely to be running cutting edge real time first person shooter games not yet anyways. I like the idea of having 128 meg for graphics. As a new programmer your not likely to push graphics unless you want to do something with photos or live streaming (Watching Live TV on your Pi).

=== SSH - Enable or disable ssh server ===

This change takes effect when???

This option enables or disables the ssh server, a program which sits quietly in the Pi looking for ssh connections from other computers. The default setting is on and there's little reason for a new user to change this unless your home network has hostile users or is open to the Internet.

ssh means 'secure shell'. It is a communication protocol which will allow you to log into the Pi from another computer on your network using a program like Putty to provide a command line interface in a terminal window.

Putty is free and available to download. It’s free Open source and runs on both Windows and Linux. You actually don't need Putty on Linux and Mac, because you can use the built-in ssh client in the Linux and Mac terminals. Just open a terminal and type 'ssh ipAddress' (replacing ipAdress with the ip of your Raspberry Pi).

This option allows access to the Pi without a monitor attached to the Pi. OK it’s easier if you have one but let’s say you want to do some command line stuff and your partner/brother/sister whatever wants to use the TV for Corrie or suchlike. Its particularly useful for starting a VNC server on the Pi so you can use the Pi's desktop on another computer. More details here [http://myraspberrypiexperience.blogspot.co.uk/p/setting-up-vnc.html]

Using Putty or the like is pretty straightforward. You will need to know the IP address of the Pi, either by watching the startup output as it scrolls by, typing sudo ifconfig at the Pi's command line or terminal window, or looking at your router. The IP address is dynamic and can change, particularly if you have not used the Pi for a day or so.

However if you are using everything from the box as is. That is to say you have your HDMI connected to a TV and a Keyboard and Mouse on the Pi and you have the menu running then I suggest you could disable ssh just to be on the safe side security wise(note just a suggestion).

=== BOOT_BEHAVIOR - Start Desktop on Boot? ===

This gives you two modes of working:

DESKTOP
When powered up the Pi will automatically log you in as pi user and display the desktop. Pressing the red Exit button on the right hand side of the screen will give the options to logout, shutdown or reboot. Logout returns to a login screen not to the command line. The command line is only accessible through a terminal window. The experience is very Windoze like, you may not need any linux commands ever, and its very quick to get to the desktop, its main downside being that since you are automatically logged in at power up there is no protection from hostile users in your household.

COMMAND LINE
When powered up the Pi stays in the command line (the big black screen). After lots of scrolling text you will be asked for your username and password. If this is successful information about the last Login is displayed which is useful for finding out if it was you, your son/daughter/grandmother/cat that was the last to login and screw up your Pi.

Then you see the standard copyright and NO WARRANTY message the latter just legalese for “your doing this at your own risk” that kind of goes without saying.

Then the key line.

Type ‘startx’ to launch graphical session

So, if at this point you type startx followed by hitting the Enter key you will be launched headlong into a windows style environment. When you have finished work Logout using the red Exit button (bottom right). Since you started from the command line this menu has only the Logout option which takes you back to the command line. To halt you must type sudo halt or to reboot sudo reboot. For halting wait until 'System Halted' is displayed before pulling the plug.

If on the other hand you want to play in the rarefied atmosphere of the command line environs then type away. You are in the home directory of the pi user; typing ls followed by [enter] will display its files and directories. Directories are in blue so type cd python_games then ls to change folder and display its contents. When you have finished don't forget to type sudo halt and wait until 'System Halted' is displayed before pulling the plug.

=== UPDATE - Try to upgrade raspi-config ===

Unless there have been recommendations on the forum by someone from the core volunteer team to use this, don't.

We could get into the Catch 22 situation where a bug is introduced into raspi-config that stopped it working. This option runs the apt-get commands to update the raspi-config software from a remote repository. You will need to be connected to the internet to use it.

=== <FINISH> ===

Use this when you have completed your changes. You will be asked whether you want to reboot or not. When used for the first time its best to reboot. This should restart your Pi. Scrolling text should appear immediately and there will be a pause if you have chosen to resize your SD card.

[[Category:RaspberryPi]]

=References=
<references/>

RPi raspi-config

2012-09-14T09:54:25Z

Meltwater: /* INFO - Information About This Tool */ - ensured how to run again is clearer

This article applies to the Wheezy Raspbian official release of 15/7/2012.

raspi-config was introduced with the advent of the Debian Wheezy image. It helps you configure your Pi. It is a work in progress so the number of menu items and the ease of use of those items will increase with time. If anyone feels willing and able to improve raspi-config then please contact Alex Bradbury [https://github.com/asb/raspi-config].

== The raspi-config ==

When you start your Pi for the first time using the Wheezy image then, following lots of scrolling text with a couple of pauses lasting in total a few tens of seconds, the raspi-config menu will appear. It has the following entries:

info Information about this tool
expand-rootfs Expand root partition to fill SD card
overscan Change overscan
configure-keyboard Set keyboard layout
change_pass Change password for ‘pi’ user
change_locale Set locale
change_timezone Set timezone
memory_split Change memory split
ssh Enable or disable ssh server
boot_behaviour Start desktop on boot?
update Try to upgrade raspi-config
<Select> <Finish>

== Moving Around the Menu ==

At any point from within any of the menu or sub-menu options the Tab key will toggle about the selected entry and the options at the bottom inside angle brackets, cursor keys move up and down menus. There is an exception to this and that’s with the change_locale option, ignore that exception for now it’s covered later.

Some of the menu entries take quite a while to display. The user experience looks like its running a desktop but in fact it isn't; its using the command line and its graphics capabilities (remember VDU's?) so occasionally the screen will scroll a bit.

== What raspi-config does ==

Some menu entries modify the file /boot/config.txt. This file, out of the box, contains a number of commented out configuration entries; raspi-config adds entries at the end of this file. You can see what raspi-config has done to the file by viewing it on the Pi using Leafpad and, if you really mess things up you can edit the file from the SD card using Notepad on a Windows PC. More information on editing config.txt here [[R-Pi_ConfigurationFile]]

Other entries modify Linux configuration files, some take effect immediately, others at the next boot.

== INFO - Information About This Tool ==

This would be really helpful if it actually explained the options in the menu, hopefully at least it will provide a reference to this Wiki page.

It helpfully advises you may have difficulties if you have heavily customized your installation but as this is probably the first thing a rookie is going to see the likelihood of a heavily customized installation is small.

== Running raspi-config another time ==
Following the first boot, your raspberry pi will boot into the command prompt or desktop (depending on your choice).

You can run it at any time after that by typing (case sensitive):
sudo raspi-config
At the command line or in a terminal window. The sudo (do as superuser) is necessary because you will be changing files that you as user pi do not own, its Debian's way of providing a root login.

The lovely thing about the Pi is that, if you mess up, it will not be difficult to re-image.

== EXPAND-ROOTFS - Expand Root Partition to Fill SD Card ==

This does what it says on the tin so if you have installed Wheezy on a 4GB or greater card use this option and AFTER REBOOT it will use all of the SD card. The Wheezy image takes nearly 2GB so if you are going to install additional software or large files its worth doing, however you don't need to do it on first boot. The downside of using all of a larger card is that it takes much longer to backup the image.

== OVERSCAN - Change Overscan ==

What would you like to do with overscan
<Disable> <Enable>

Any changes will take effect after a reboot. If you change a setting and end up losing the left side of the screen you can easily edit /boot/config.txt on a PC to undo the changes.

Televisions do not usually display the whole of the picture, they Overscan and crop off a few percent of the image. This is to hide the data signals such as teletext which use the outer lines of the picture (could be a hangover from analogue TV). Computers, including the Pi, use all the lines for real display so often the image displayed by computers on TV's is cropped.

To avoid losing the critical left column at first boot the clever Pi people have deliberately enabled Overscan and used positive Overscan vlauses to make the displayed image smaller, and to play safe much smaller. This means, depending on your monitor/TV, there may be black borders around the picture. LXDE will show the wrong resolution in its display information as it shows you the size of the framebuffer (display_size - overscan).

On some displays, particularly monitors, just disabling Overscan will make the picture fill the whole screen and correct the resolution. For other displays it may be necessary to leave overscan enabled and fiddle with Overscan values, more information here [[R-Pi_Troubleshooting#Big_black_borders_around_small_image_on_HD_monitors]].

== CONFIGURE-KEYBOARD - Set keyboard layout ==

Slow to display and, if you select some of the non-default options, there will be a short delay while changes are made. Changes take effect immediately except for changes to X-server exit which require a reboot.

This menu for using different attached keyboards. Brands of keyboards are chosen first followed by other choices to set up nationality of keyboards etc.

Default is Generic 105-key (Intl) PC. If you cannot find your keyboard on the list then use one of the generic keyboards but it’s probably not a big deal if you can't find yours on the list, have fun remember you can always, change it later or re-image if you're really stuck.

The next screen regards keyboard layout. If you are not using the first choice of English UK select Other and you will be faced with a long list of other national keyboards. Funnily enough this list includes English UK.

Next screen is quite well documented on the screen you're probably going to run with one of the top two choices. These are:

The default for the keyboard layout
Or
No AltGr key

To be honest if this is your first setup and you get this wrong it’s not going to break the bank and as I keep saying if in doubt re-image and start again.

Next screen; well if your using a standard keyboard then you probably don’t have a compose key and if your new to computing as intended you're not likely to need one for a while so I would suggest choosing

No compose key

The next screen is a useful one and the on screen documentation is actually quite clear provided you know what is meant by “X server” so here’s an outline:

If you choose to boot to the command line (see later) then after login the Pi will tell you that you can run startx. Startx is the command to run the windows (like) screen where you use a mouse to select options.

This is the X server and to get back to command line (that’s all the typed stuff) you can use [Ctrl][Alt][Backspace] all pressed at the same time to shut down this X server screen; you can always restart it by typing “startx”. Always handy if you have a flaky mouse or are using a wireless mouse that eats batteries.

Of course this is pointless if you don’t remember the key combination when the time comes!

== CHANGE_PASS - Change password for ‘pi’ user ==

The default user for the Wheezy install is pi and its password is raspberry. Until you're familiar with the setup it’s probably better to leave this password as it is at least till you are happy changing stuff. In addition you can re-run raspi-config to change it at any time.

If you screw this up be prepared to re-image and lose any work you have done and programs installed (you did back up your data didn't you). With Linux and Unix forgotten passwords are a killer the Raspberry Pi is one of the simpler systems. Let's face it till you know what your looking at, the out of the box solution of pi and raspberry are probably all you will need.

== CHANGE_LOCALE - Set locale ==

Slow to start up and there will be a delay while locales are generated.

You can tell this was written by a computer engineer and not a human how about this as an alternative.

change_locale Tell the computer if you need non English characters.

Sheesh! a computer aimed at children and new users and then you expect them to know what locale means (Google's your friend?).

This menu option gives you a massive list of choices that look like they were written by one of the infinite monkeys of legend (goggle infinite monkeys Shakespeare if you don’t understand this reference).

The default setting is

en_GB UTF-8 UTF-8 (ain't it nice to have a UK produced computer!)

English, Great Britain and UTF-8 is a code related to showing all of the characters usually needed to show English letters and other symbols on the screen. If you are working in some other language than English then you will probably need to play around with this.

You can select multiple choices in the list the space bar toggles them on and off (this was the exception I mentioned earlier) and it’s a long list. Basically if you want to work in more than one language then you will need to make other choices from this list based on the languages you intend to use.

If you are working in English only the default choice is probably the only one you will need.

== CHANGE_TIMEZONE - Set timezone ==

Slow to display.

This is where you setup your clock; now it’s no big issue if it’s wrong it just means the date and time assigned to files you create (automatically when you make them) will be out and its not hard to set this up. (What is the effect if you are not connected to the internet and don't have time set with ntp?)

The set up consists of two layers basically to make your selection easier to find.

First option screen think Continent; just to confuse things you have US and America because we all know USA is not part of America. Actually the US option just gives you a shorter list containing the US time zones that are included in the American list; they just made a shorter list under US for all those Good Old Boy American Citizens who don’t know about American places outside of the USA. (flames imminent!).

SystemV relies on you knowing what SystemV is (Think Unix and ignore it for now).

Most people know where they are in the world for time zone; for me it’s Europe then London on the next screen but I’ve always been of the opinion that there should be ropes and lights around the M25 with signs saying “Danger hole in the world Keep Out” but then I’m not from London and the M25 was always the road to hell.

== MEMORY_SPLIT - Change memory split ==

This allows you to choose how much of the RAM memory is set aside for the Broadcom Graphics Processing Unit (Videocore) and how much for the operation of the main ARM processor.

Three choices 32MiB for Videocore, 64MiB for Videocore, 128MiB for Videocore. First time users should leave it at the default 64MiB for the Videocore. There is more information on when to use the different options here [[RPi_Advanced_Setup]]. You can change it with raspi-config and it will take effect at the next reboot (check).

Now let’s assume your really fresh to writing code, as in never done this before ever. You're not going to be writing really complex Artificial Intelligence type programs and your also unlikely to be running cutting edge real time first person shooter games not yet anyways. I like the idea of having 128 meg for graphics. As a new programmer your not likely to push graphics unless you want to do something with photos or live streaming (Watching Live TV on your Pi).

== SSH - Enable or disable ssh server ==

This change takes effect when???

This option enables or disables the ssh server, a program which sits quietly in the Pi looking for ssh connections from other computers. The default setting is on and there's little reason for a new user to change this unless your home network has hostile users or is open to the Internet.

ssh means 'secure shell'. It is a communication protocol which will allow you to log into the Pi from another computer on your network using a program like Putty to provide a command line interface in a terminal window.

Putty is free and available to download. It’s free Open source and runs on both Windows and Linux. You actually don't need Putty on Linux and Mac, because you can use the built-in ssh client in the Linux and Mac terminals. Just open a terminal and type 'ssh ipAddress' (replacing ipAdress with the ip of your Raspberry Pi).

This option allows access to the Pi without a monitor attached to the Pi. OK it’s easier if you have one but let’s say you want to do some command line stuff and your partner/brother/sister whatever wants to use the TV for Corrie or suchlike. Its particularly useful for starting a VNC server on the Pi so you can use the Pi's desktop on another computer. More details here [http://myraspberrypiexperience.blogspot.co.uk/p/setting-up-vnc.html]

Using Putty or the like is pretty straightforward. You will need to know the IP address of the Pi, either by watching the startup output as it scrolls by, typing sudo ifconfig at the Pi's command line or terminal window, or looking at your router. The IP address is dynamic and can change, particularly if you have not used the Pi for a day or so.

However if you are using everything from the box as is. That is to say you have your HDMI connected to a TV and a Keyboard and Mouse on the Pi and you have the menu running then I suggest you could disable ssh just to be on the safe side security wise(note just a suggestion).

== BOOT_BEHAVIOR - Start Desktop on Boot? ==

This gives you two modes of working:

DESKTOP
When powered up the Pi will automatically log you in as pi user and display the desktop. Pressing the red Exit button on the right hand side of the screen will give the options to logout, shutdown or reboot. Logout returns to a login screen not to the command line. The command line is only accessible through a terminal window. The experience is very Windoze like, you may not need any linux commands ever, and its very quick to get to the desktop, its main downside being that since you are automatically logged in at power up there is no protection from hostile users in your household.

COMMAND LINE
When powered up the Pi stays in the command line (the big black screen). After lots of scrolling text you will be asked for your username and password. If this is successful information about the last Login is displayed which is useful for finding out if it was you, your son/daughter/grandmother/cat that was the last to login and screw up your Pi.

Then you see the standard copyright and NO WARRANTY message the latter just legalese for “your doing this at your own risk” that kind of goes without saying.

Then the key line.

Type ‘startx’ to launch graphical session

So, if at this point you type startx followed by hitting the Enter key you will be launched headlong into a windows style environment. When you have finished work Logout using the red Exit button (bottom right). Since you started from the command line this menu has only the Logout option which takes you back to the command line. To halt you must type sudo halt or to reboot sudo reboot. For halting wait until 'System Halted' is displayed before pulling the plug.

If on the other hand you want to play in the rarefied atmosphere of the command line environs then type away. You are in the home directory of the pi user; typing ls followed by [enter] will display its files and directories. Directories are in blue so type cd python_games then ls to change folder and display its contents. When you have finished don't forget to type sudo halt and wait until 'System Halted' is displayed before pulling the plug.

== UPDATE - Try to upgrade raspi-config ==

Unless there have been recommendations on the forum by someone from the core volunteer team to use this, don't.

We could get into the Catch 22 situation where a bug is introduced into raspi-config that stopped it working. This option runs the apt-get commands to update the raspi-config software from a remote repository. You will need to be connected to the internet to use it.

== <FINISH> ==

Use this when you have completed your changes. You will be asked whether you want to reboot or not. When used for the first time its best to reboot. This should restart your Pi. Scrolling text should appear immediately and there will be a pause if you have chosen to resize your SD card.

[[Category:RaspberryPi]]

=References=
<references/>

RPi HardwareHistory

2012-09-05T08:57:36Z

Meltwater: /* F1 & F2 Replacement/Removal */

[[Category:RaspberryPi]]
{{Template:RPi_Hardware}}

==Board Revision History==
Find out your board revision with the following command:
cat /proc/cpuinfo
You will see your device data including:
Hardware : BCM2708
Revision : 0003

Newest revision at the top of the list.

{| border="1"
! Release Date
! Model A/B
! PCB Revision
! Build Revision
! Notes
|-
| N/A
| A
| 1.0
| None
| ECN0001
|-
| Q3 2012
| B
| 1.0
| 0003
| ECN0001
|-
| N/A
| A
| 1.0
| None
|
|-
| Q1 2012
| B
| 1.0
| 0002
|
|-
| Q1 2012
| B
| Beta
| Beta
| Beta Board
|}

*The model A's do not have a board revision number, as they are not released at present

===ECN0001===
ECN0001 is the request to not fit D14 and replace F1 and F2 with 0 ohm.
====D14 Removal====
D14 can interfere with some CEC devices if the Pi is left plugged in and unpowered. The benefits of having it are minimal so it was removed.<ref name="D14">[http://www.raspberrypi.org/phpBB3/viewtopic.php?f=63&t=16365 New Pi missing D14]</ref>

====F1 & F2 Replacement/Removal====
F1 & F2 can cause problems with some USB devices which draw high current. In particular due to the recovery characteristics of the Poly-fuses, it can take a while to recover their low resistance state afterwards, adding additional problems for other devices (lower voltage on the USB bus).

==Raspberry Pi Model-A Full Production Board ==
* Announced: Not Yet (as of 16 June 2012)
* Board will now have 256Mb of RAM rather than the originally planned 128Mb<ref name="postSale">[http://www.raspberrypi.org/archives/723 Post-Launch - And breathe…]</ref>
* Foundation will probably produce a small Beta batch before handing manufacturing over to RS and Farnell

==Raspberry Pi Model-B Full Production Board ==
[[File:RaspiFront.JPG|250px|thumb|right|The Rpi full production board (model B)]]
* Announced: April 2012, first orders sent out June 2012.
* Manufacturing and Orders will be made through RS and Farnell
* This means a much higher volume of units will be produced and made available.
* Additional detail is available about the manufacturing and distribution agreement here [http://hardware.slashdot.org/story/12/02/28/2347222/raspberry-pi-now-has-distributors----and-will-soon-have-boards-for-all-video video interview between Eben Upton and SlashDot here (28/02/12)].

==Raspberry Pi 1st Production Board ==
* Announced: 29th Feb 2012 - Start of Sale Only<ref name="postSale"/>
* Credit-card Format
* Initial 10k Batch (All Model-B's) Manufactured in China (Jan/Feb 2012)<ref name="firstProduction" >[http://www.raspberrypi.org/archives/509 We’ve started manufacture!]</ref>
* Should look identical to the Raspberry Pi Beta Board below (except different SDCard holder).
* The board has a yellow RCA connector, rather than the black one used in the Beta's.
* Nokia/Qt Development group has donated vouchers for 400 RPi units for developers<ref name="nokiaDonate">[http://www.raspberrypi.org/archives/369 Nokia has Raspberry Pi vouchers for 400 Qt developers]</ref>
* The batch was delayed several weeks due to the RJ45 network connector being substituted for the wrong part<ref>[http://www.raspberrypi.org/archives/781 Manufacturing Hiccup]</ref> and also so the board could undergo compliance testing<ref>[http://www.raspberrypi.org/archives/852 Compliance testing]</ref>

==Raspberry Pi Beta Production Board ==
[[File:RpiFront.jpg|250px|thumb|right|The Rpi beta board (model B)]]
* Announced: December 2011<ref name="#Beta">[http://www.raspberrypi.org/archives/422 Populated boards: an update on where we are]</ref>
* Credit-Card Format
* Manufactured in UK
* Produced 100<ref name="betapcb">[http://www.raspberrypi.org/archives/389 We have PCBs! BETA]</ref> PCBs
* Characteristic feature of hand-modded correction to PCB <ref name="betaError">[http://www.raspberrypi.org/archives/470 (hand-mod) More on the beta boards]</ref>
* See the [http://www.raspberrypi.org/archives/482 blog post] which includes a video explaining how the production units will differ from the beta boards.

* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-002-copy2-e1322775411416.jpg Pre-production board (beta board) PCB, topside]
* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-003-copy2.jpg Pre-production board (beta board) PCB, underside]
* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-001-copy.jpg Pre-production board vs credit-card]

===eBay Auction===
10 of the completed Model-B boards were auctioned on eBay (Started on 1st Jan 2012) <ref name="betaebay">[http://www.raspberrypi.org/archives/482 We’re auctioning ten beta Raspberry Pis!]</ref>)
{| border="1"
|SerialNo:
|#1
|#2
|#3
|#4
|#5
|#6
|#7<ref name="#7Donated"/>
|#8<ref name="#8PaulMaunders"/>
|#9
|#10
|-
|Date:
|11-Jan-2012
|11-Jan-2012
|10-Jan-2012
|10-Jan-2012
|09-Jan-2012
|09-Jan-2012
|08-Jan-2012
|08-Jan-2012
|07-Jan-2012
|07-Jan-2012
|-
|Sold For:
|£3,500
|£2,150
|£2,257
|£1,550
|£1,040
|£1,000
|£989
|£1,020
|£930
|£1,900
|}
Board #7 was anonymously (and generously) donated to [http://www.computinghistory.org.uk/ Centre for Computing History]<ref name="#7Donated">[http://www.raspberrypi.org/archives/503 Beta board bought by anonymous bidder and donated to museum]</ref> (also spotted [http://twitpic.com/86trra here..])!

Board #8 Owned by Tech Blogger, Paul Maunders, see his [http://www.pyrosoft.co.uk/blog blog] for details<ref name="#8PaulMaunders">[http://www.pyrosoft.co.uk/blog/2012/01/13/raspberry-pi-8-first-photoshoot/ Paul Maunders - Raspberry Pi #8 First Photoshoot]</ref>

==Raspberry Pi Alpha Board ==
[[File:RPi-alpha.jpg|250px|thumb|right|RPi Alpha Board]]

* Announced: August 2011<ref name="#Alpha">[http://www.raspberrypi.org/archives/78 The alpha boards are here!]</ref>
* Large Format for debugging (Model-B)
* Populated with headers for GPIO, JTAG, DSI, CSI, as well as switches and LEDs for I/O testing.

* [http://www.raspberrypi.org/wp-content/uploads/2011/08/DSCF1809.jpg Alpha prototype board, underside]

==Raspberry Pi USB Prototype Board ==
[[File:Rpi-usbproto.jpg|250px|thumb|right|RPi USB Prototype Board]]
* Announced: May 2011
* The "Computer On A USB Stick" Format
* Included built-in camera
* HDMI one end and single USB the other
* Introduced the RPi Foundation to the world (any earlier links appreciated), featured by [http://www.bbc.co.uk/news/technology-13292450 BBC Online Video].

‎

==Raspberry Pi Concept 2006 edition==
[[File:RPi-atmel2006Ed.jpg|250px|thumb|right|Raspberry Pi Concept 2006 edition]]
* Vero-board Prototype & PCB Version
* Atmel ATmega644 microcontroller clocked at 22.1MHz<ref name="2006ed">[http://www.raspberrypi.org/archives/264 Raspberry Pi – 2006 edition]</ref>

==See Also==
===Video===
* [http://news.bbc.co.uk/1/hi/programmes/click_online/9504208.stm BBC iClick's Peter Price asks whether a £15 computer can solve the programming gap] (6 minutes, 3 June 2011)
* [http://www.youtube.com/watch?v=pQ7N4rycsy4 Raspberry Pi's David Braben talks to BBC's Rory Cellan-Jones] (2:28 minutes, 5 May 2011)
* [http://www.youtube.com/RaspberryPiTutorials Raspberry Pi community tutorials on YouTube]

===Audio===
* [http://foundationlibraries.blogspot.com/2011/06/cfl-podcast-eben-upton-raspberry-pi.html Podcast of a phone interview with Eben about the project and the motivations behind it] (15 minutes long.) (3 June 2011) Transcription [http://tomhannen.posterous.com/raspberry-pi-podcast-transcript here].

==References==
<references/>

{{Template:Raspberry Pi}}

RPi HardwareHistory

2012-09-05T08:56:52Z

Meltwater: /* Board Revision History */

[[Category:RaspberryPi]]
{{Template:RPi_Hardware}}

==Board Revision History==
Find out your board revision with the following command:
cat /proc/cpuinfo
You will see your device data including:
Hardware : BCM2708
Revision : 0003

Newest revision at the top of the list.

{| border="1"
! Release Date
! Model A/B
! PCB Revision
! Build Revision
! Notes
|-
| N/A
| A
| 1.0
| None
| ECN0001
|-
| Q3 2012
| B
| 1.0
| 0003
| ECN0001
|-
| N/A
| A
| 1.0
| None
|
|-
| Q1 2012
| B
| 1.0
| 0002
|
|-
| Q1 2012
| B
| Beta
| Beta
| Beta Board
|}

*The model A's do not have a board revision number, as they are not released at present

===ECN0001===
ECN0001 is the request to not fit D14 and replace F1 and F2 with 0 ohm.
====D14 Removal====
D14 can interfere with some CEC devices if the Pi is left plugged in and unpowered. The benefits of having it are minimal so it was removed.<ref name="D14">[http://www.raspberrypi.org/phpBB3/viewtopic.php?f=63&t=16365 New Pi missing D14]</ref>

====F1 & F2 Replacement/Removal====
F1 & F2 can cause problems with some USB devices which draw high current. In particular due to the recovery characteristics of the Poly-fuses, it can take a while to recover their low resistance state afterwards, adding additional problems for other devices.

==Raspberry Pi Model-A Full Production Board ==
* Announced: Not Yet (as of 16 June 2012)
* Board will now have 256Mb of RAM rather than the originally planned 128Mb<ref name="postSale">[http://www.raspberrypi.org/archives/723 Post-Launch - And breathe…]</ref>
* Foundation will probably produce a small Beta batch before handing manufacturing over to RS and Farnell

==Raspberry Pi Model-B Full Production Board ==
[[File:RaspiFront.JPG|250px|thumb|right|The Rpi full production board (model B)]]
* Announced: April 2012, first orders sent out June 2012.
* Manufacturing and Orders will be made through RS and Farnell
* This means a much higher volume of units will be produced and made available.
* Additional detail is available about the manufacturing and distribution agreement here [http://hardware.slashdot.org/story/12/02/28/2347222/raspberry-pi-now-has-distributors----and-will-soon-have-boards-for-all-video video interview between Eben Upton and SlashDot here (28/02/12)].

==Raspberry Pi 1st Production Board ==
* Announced: 29th Feb 2012 - Start of Sale Only<ref name="postSale"/>
* Credit-card Format
* Initial 10k Batch (All Model-B's) Manufactured in China (Jan/Feb 2012)<ref name="firstProduction" >[http://www.raspberrypi.org/archives/509 We’ve started manufacture!]</ref>
* Should look identical to the Raspberry Pi Beta Board below (except different SDCard holder).
* The board has a yellow RCA connector, rather than the black one used in the Beta's.
* Nokia/Qt Development group has donated vouchers for 400 RPi units for developers<ref name="nokiaDonate">[http://www.raspberrypi.org/archives/369 Nokia has Raspberry Pi vouchers for 400 Qt developers]</ref>
* The batch was delayed several weeks due to the RJ45 network connector being substituted for the wrong part<ref>[http://www.raspberrypi.org/archives/781 Manufacturing Hiccup]</ref> and also so the board could undergo compliance testing<ref>[http://www.raspberrypi.org/archives/852 Compliance testing]</ref>

==Raspberry Pi Beta Production Board ==
[[File:RpiFront.jpg|250px|thumb|right|The Rpi beta board (model B)]]
* Announced: December 2011<ref name="#Beta">[http://www.raspberrypi.org/archives/422 Populated boards: an update on where we are]</ref>
* Credit-Card Format
* Manufactured in UK
* Produced 100<ref name="betapcb">[http://www.raspberrypi.org/archives/389 We have PCBs! BETA]</ref> PCBs
* Characteristic feature of hand-modded correction to PCB <ref name="betaError">[http://www.raspberrypi.org/archives/470 (hand-mod) More on the beta boards]</ref>
* See the [http://www.raspberrypi.org/archives/482 blog post] which includes a video explaining how the production units will differ from the beta boards.

* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-002-copy2-e1322775411416.jpg Pre-production board (beta board) PCB, topside]
* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-003-copy2.jpg Pre-production board (beta board) PCB, underside]
* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-001-copy.jpg Pre-production board vs credit-card]

===eBay Auction===
10 of the completed Model-B boards were auctioned on eBay (Started on 1st Jan 2012) <ref name="betaebay">[http://www.raspberrypi.org/archives/482 We’re auctioning ten beta Raspberry Pis!]</ref>)
{| border="1"
|SerialNo:
|#1
|#2
|#3
|#4
|#5
|#6
|#7<ref name="#7Donated"/>
|#8<ref name="#8PaulMaunders"/>
|#9
|#10
|-
|Date:
|11-Jan-2012
|11-Jan-2012
|10-Jan-2012
|10-Jan-2012
|09-Jan-2012
|09-Jan-2012
|08-Jan-2012
|08-Jan-2012
|07-Jan-2012
|07-Jan-2012
|-
|Sold For:
|£3,500
|£2,150
|£2,257
|£1,550
|£1,040
|£1,000
|£989
|£1,020
|£930
|£1,900
|}
Board #7 was anonymously (and generously) donated to [http://www.computinghistory.org.uk/ Centre for Computing History]<ref name="#7Donated">[http://www.raspberrypi.org/archives/503 Beta board bought by anonymous bidder and donated to museum]</ref> (also spotted [http://twitpic.com/86trra here..])!

Board #8 Owned by Tech Blogger, Paul Maunders, see his [http://www.pyrosoft.co.uk/blog blog] for details<ref name="#8PaulMaunders">[http://www.pyrosoft.co.uk/blog/2012/01/13/raspberry-pi-8-first-photoshoot/ Paul Maunders - Raspberry Pi #8 First Photoshoot]</ref>

==Raspberry Pi Alpha Board ==
[[File:RPi-alpha.jpg|250px|thumb|right|RPi Alpha Board]]

* Announced: August 2011<ref name="#Alpha">[http://www.raspberrypi.org/archives/78 The alpha boards are here!]</ref>
* Large Format for debugging (Model-B)
* Populated with headers for GPIO, JTAG, DSI, CSI, as well as switches and LEDs for I/O testing.

* [http://www.raspberrypi.org/wp-content/uploads/2011/08/DSCF1809.jpg Alpha prototype board, underside]

==Raspberry Pi USB Prototype Board ==
[[File:Rpi-usbproto.jpg|250px|thumb|right|RPi USB Prototype Board]]
* Announced: May 2011
* The "Computer On A USB Stick" Format
* Included built-in camera
* HDMI one end and single USB the other
* Introduced the RPi Foundation to the world (any earlier links appreciated), featured by [http://www.bbc.co.uk/news/technology-13292450 BBC Online Video].

‎

==Raspberry Pi Concept 2006 edition==
[[File:RPi-atmel2006Ed.jpg|250px|thumb|right|Raspberry Pi Concept 2006 edition]]
* Vero-board Prototype & PCB Version
* Atmel ATmega644 microcontroller clocked at 22.1MHz<ref name="2006ed">[http://www.raspberrypi.org/archives/264 Raspberry Pi – 2006 edition]</ref>

==See Also==
===Video===
* [http://news.bbc.co.uk/1/hi/programmes/click_online/9504208.stm BBC iClick's Peter Price asks whether a £15 computer can solve the programming gap] (6 minutes, 3 June 2011)
* [http://www.youtube.com/watch?v=pQ7N4rycsy4 Raspberry Pi's David Braben talks to BBC's Rory Cellan-Jones] (2:28 minutes, 5 May 2011)
* [http://www.youtube.com/RaspberryPiTutorials Raspberry Pi community tutorials on YouTube]

===Audio===
* [http://foundationlibraries.blogspot.com/2011/06/cfl-podcast-eben-upton-raspberry-pi.html Podcast of a phone interview with Eben about the project and the motivations behind it] (15 minutes long.) (3 June 2011) Transcription [http://tomhannen.posterous.com/raspberry-pi-podcast-transcript here].

==References==
<references/>

{{Template:Raspberry Pi}}

RPi HardwareHistory

2012-09-05T08:54:49Z

Meltwater: /* Raspberry Pi Model-A Full Production Board */

[[Category:RaspberryPi]]
{{Template:RPi_Hardware}}

==Board Revision History==
Find out your board revision with the following command:
cat /proc/cpuinfo
You will see your device data including:
Hardware : BCM2708
Revision : 0003

Newest revision at the top of the list.

{| border="1"
! Release Date
! Model A/B
! PCB Revision
! Build Revision
! Notes
|-
| N/A
| A
| 1.0
| None
| ECN0001
|-
| Q3 2012
| B
| 1.0
| 0003
| ECN0001
|-
| N/A
| A
| 1.0
| None
|
|-
| Q1 2012
| B
| 1.0
| 0002
|
|-
| Q1 2012
| B
| Beta
| Beta
| Beta Board
|}

*The model A's do not have board revision number, as they are not released at present

===ECN0001===
ECN0001 is the request to not fit D14 and replace F1 and F2 with 0 ohm.
====D14 Removal====
D14 can interfere with some CEC devices if the Pi is left plugged in and unpowered. The benefits of having it are minimal so it was removed.<ref name="D14">[http://www.raspberrypi.org/phpBB3/viewtopic.php?f=63&t=16365 New Pi missing D14]</ref>

====F1 & F2 Replacement/Removal====
F1 & F2 can cause problems with some USB devices which draw high current. In particular due to the recovery characteristics of the Poly-fuses, it can take a while to recover their low resistance state afterwards, adding additional problems for other devices.

==Raspberry Pi Model-A Full Production Board ==
* Announced: Not Yet (as of 16 June 2012)
* Board will now have 256Mb of RAM rather than the originally planned 128Mb<ref name="postSale">[http://www.raspberrypi.org/archives/723 Post-Launch - And breathe…]</ref>
* Foundation will probably produce a small Beta batch before handing manufacturing over to RS and Farnell

==Raspberry Pi Model-B Full Production Board ==
[[File:RaspiFront.JPG|250px|thumb|right|The Rpi full production board (model B)]]
* Announced: April 2012, first orders sent out June 2012.
* Manufacturing and Orders will be made through RS and Farnell
* This means a much higher volume of units will be produced and made available.
* Additional detail is available about the manufacturing and distribution agreement here [http://hardware.slashdot.org/story/12/02/28/2347222/raspberry-pi-now-has-distributors----and-will-soon-have-boards-for-all-video video interview between Eben Upton and SlashDot here (28/02/12)].

==Raspberry Pi 1st Production Board ==
* Announced: 29th Feb 2012 - Start of Sale Only<ref name="postSale"/>
* Credit-card Format
* Initial 10k Batch (All Model-B's) Manufactured in China (Jan/Feb 2012)<ref name="firstProduction" >[http://www.raspberrypi.org/archives/509 We’ve started manufacture!]</ref>
* Should look identical to the Raspberry Pi Beta Board below (except different SDCard holder).
* The board has a yellow RCA connector, rather than the black one used in the Beta's.
* Nokia/Qt Development group has donated vouchers for 400 RPi units for developers<ref name="nokiaDonate">[http://www.raspberrypi.org/archives/369 Nokia has Raspberry Pi vouchers for 400 Qt developers]</ref>
* The batch was delayed several weeks due to the RJ45 network connector being substituted for the wrong part<ref>[http://www.raspberrypi.org/archives/781 Manufacturing Hiccup]</ref> and also so the board could undergo compliance testing<ref>[http://www.raspberrypi.org/archives/852 Compliance testing]</ref>

==Raspberry Pi Beta Production Board ==
[[File:RpiFront.jpg|250px|thumb|right|The Rpi beta board (model B)]]
* Announced: December 2011<ref name="#Beta">[http://www.raspberrypi.org/archives/422 Populated boards: an update on where we are]</ref>
* Credit-Card Format
* Manufactured in UK
* Produced 100<ref name="betapcb">[http://www.raspberrypi.org/archives/389 We have PCBs! BETA]</ref> PCBs
* Characteristic feature of hand-modded correction to PCB <ref name="betaError">[http://www.raspberrypi.org/archives/470 (hand-mod) More on the beta boards]</ref>
* See the [http://www.raspberrypi.org/archives/482 blog post] which includes a video explaining how the production units will differ from the beta boards.

* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-002-copy2-e1322775411416.jpg Pre-production board (beta board) PCB, topside]
* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-003-copy2.jpg Pre-production board (beta board) PCB, underside]
* [http://www.raspberrypi.org/wp-content/uploads/2011/12/Picture-001-copy.jpg Pre-production board vs credit-card]

===eBay Auction===
10 of the completed Model-B boards were auctioned on eBay (Started on 1st Jan 2012) <ref name="betaebay">[http://www.raspberrypi.org/archives/482 We’re auctioning ten beta Raspberry Pis!]</ref>)
{| border="1"
|SerialNo:
|#1
|#2
|#3
|#4
|#5
|#6
|#7<ref name="#7Donated"/>
|#8<ref name="#8PaulMaunders"/>
|#9
|#10
|-
|Date:
|11-Jan-2012
|11-Jan-2012
|10-Jan-2012
|10-Jan-2012
|09-Jan-2012
|09-Jan-2012
|08-Jan-2012
|08-Jan-2012
|07-Jan-2012
|07-Jan-2012
|-
|Sold For:
|£3,500
|£2,150
|£2,257
|£1,550
|£1,040
|£1,000
|£989
|£1,020
|£930
|£1,900
|}
Board #7 was anonymously (and generously) donated to [http://www.computinghistory.org.uk/ Centre for Computing History]<ref name="#7Donated">[http://www.raspberrypi.org/archives/503 Beta board bought by anonymous bidder and donated to museum]</ref> (also spotted [http://twitpic.com/86trra here..])!

Board #8 Owned by Tech Blogger, Paul Maunders, see his [http://www.pyrosoft.co.uk/blog blog] for details<ref name="#8PaulMaunders">[http://www.pyrosoft.co.uk/blog/2012/01/13/raspberry-pi-8-first-photoshoot/ Paul Maunders - Raspberry Pi #8 First Photoshoot]</ref>

==Raspberry Pi Alpha Board ==
[[File:RPi-alpha.jpg|250px|thumb|right|RPi Alpha Board]]

* Announced: August 2011<ref name="#Alpha">[http://www.raspberrypi.org/archives/78 The alpha boards are here!]</ref>
* Large Format for debugging (Model-B)
* Populated with headers for GPIO, JTAG, DSI, CSI, as well as switches and LEDs for I/O testing.

* [http://www.raspberrypi.org/wp-content/uploads/2011/08/DSCF1809.jpg Alpha prototype board, underside]

==Raspberry Pi USB Prototype Board ==
[[File:Rpi-usbproto.jpg|250px|thumb|right|RPi USB Prototype Board]]
* Announced: May 2011
* The "Computer On A USB Stick" Format
* Included built-in camera
* HDMI one end and single USB the other
* Introduced the RPi Foundation to the world (any earlier links appreciated), featured by [http://www.bbc.co.uk/news/technology-13292450 BBC Online Video].

‎

==Raspberry Pi Concept 2006 edition==
[[File:RPi-atmel2006Ed.jpg|250px|thumb|right|Raspberry Pi Concept 2006 edition]]
* Vero-board Prototype & PCB Version
* Atmel ATmega644 microcontroller clocked at 22.1MHz<ref name="2006ed">[http://www.raspberrypi.org/archives/264 Raspberry Pi – 2006 edition]</ref>

==See Also==
===Video===
* [http://news.bbc.co.uk/1/hi/programmes/click_online/9504208.stm BBC iClick's Peter Price asks whether a £15 computer can solve the programming gap] (6 minutes, 3 June 2011)
* [http://www.youtube.com/watch?v=pQ7N4rycsy4 Raspberry Pi's David Braben talks to BBC's Rory Cellan-Jones] (2:28 minutes, 5 May 2011)
* [http://www.youtube.com/RaspberryPiTutorials Raspberry Pi community tutorials on YouTube]

===Audio===
* [http://foundationlibraries.blogspot.com/2011/06/cfl-podcast-eben-upton-raspberry-pi.html Podcast of a phone interview with Eben about the project and the motivations behind it] (15 minutes long.) (3 June 2011) Transcription [http://tomhannen.posterous.com/raspberry-pi-podcast-transcript here].

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Tutorial EGHS:GPIO Protection Circuits

2012-07-06T08:47:50Z

Meltwater: /* Physical Pin Protection */

{{Template:RPi Tutorials}}

''This page is part of a work in progress.''

==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==
In order to protect the Raspberry Pi hardware, it is highly recommended that the GPIO pins are protected in some form to avoid damage. This page will introduce some circuits which can be used to protect the pins.

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

THIS PAGE IS UNDER-CONSTRUCTION AND UNTESTED ON RASPBERRY PI HARDWARE

==Why protect the pins?==
While the GPIO pins can provide lots of useful control and sensing ability to the Raspberry Pi, it is important to remember they are wired directly into the internal core of the system. This means that they provide a very easy way to introduce bad voltages and currents into the delicate heart of the Raspberry Pi (this is not good and means it is easy to break it without exercising a little care).

Things we need to protect:

1) Drawing excess current from the pins (or short-circuiting an output)

2) Driving over-voltage on an input pin (anything above 3.3V should be avoided)

3) Static shocks, from touching pins without suitable grounding (often called ESD - ElectroStatic Discharge, occurs when your clothes etc build up an electrical charge as you move around)

All of these can potentially break your Raspberry Pi, damage the GPIO circuits or weaken it over time (reducing its overall life).

==Physical Pin Protection==
You must remember that the GPIO pin connections ([[RPi Low-level peripherals#General Purpose Input/Output (GPIO) | General Purpose Input/Output (GPIO)]]) also carry 3.3V, 5V and GND on the same 2x13pin header, so care must be taken when connecting and disconnecting wires that you don't accidentally connect these pins (i.e. 5V passed onto the GND or connected to 3.3V is likely to cause problems - if you are lucky the Polyfuse will kick in (can take an hour or so to reset), if you are unlucky you may break something permanently.

There are a number of ways to do this (depending on your requirements), such as using some jumpers (see photo) set to one side, strips of wire insulation (ideal for the NC - non-connection pins) or by using a full ribbon cable connector (like those used on IDE hard drives).

Photos required

Guides:

[http://www.raspberrypi.org/archives/1404 Hardware lesson with Gert: make your own ribbon cable connector]

Also the [http://www.themagpi.com MagPi] features a photo guide in '''[http://issuu.com/themagpi/docs/the_magpi_issue_3_final Issue 3 July 2012 (flash version)]''' - Pages 16-19.

==Protection Circuits==
There are many ways to protect the GPIO pins electrically, below explains some of the methods.

In many cases, the selected IC will also have electrical limits of their own (hopefully less restrictive than the Raspberry Pi), so you may end up blowing them instead. However, it is preferable to replace an IC (of less value and greater availability) which has been blown than to break your Raspberry Pi.

Please expand these sections with more information about options available
and why some are better than others.

If you are planning on using some of these circuits, it is recommended you research similar circuits to determine the best configuration for your needs.

===Zener Diode Protection===
This method uses a 3.3V Zener diode to limit the voltage which will be applied to the GPIO pins. By placing the diode between the GPIO pin and Gnd, any voltage applied which is greater than 3.3V will cause the Zener diode to "break down" (allow current to flow) through diode to Gnd (ensuring the voltage that reaches the GPIO is no more than 3.3V. Although there are cases where this protection won't fully save the GPIO from damage, it is highly recommended to protect from common wiring errors.

Example Circuit:

[http://www.thebox.myzen.co.uk/Raspberry/Breakout.html Mike Cook's Raspberry Pi Breakout Board]

===Transistor Switch===
See the second part of the [[RPi Tutorial EGHS:LED output#Circuit 2 - LED Driving Circuit (using Transistor Switching Circuit) | LED Driving Circuit (using Transistor Switching Circuit)]].

===Transistor Logic Shifters===
As well as providing protection, logic shifters will allow you to safely mix circuits which use different logic voltages. For instance many I2C (a common protocol) devices use 5V logic, so a level shifter is required to interface them with the RPi. If you always intend using the level shifter with the RPi, then using Zener diodes as mentioned above, on the low-voltage supply is probably a good idea too.

Other information on Logic level shifters (use only as a guide, particularly regarding the "out-of-specs" section):

[http://arduino.cc/playground/Main/I2CBi-directionalLevelShifter Arduino.cc I2C bi-directional level shifter]

[http://www.nxp.com/documents/application_note/AN10441.pdf NXP's Application Note AN10441 Level shifting techniques in I2C-bus design]

Example Circuit:

[http://www.sparkfun.com/products/8745 Sparkfun's Logic Level Converter] - Product linked only because they also provide schematics so you can make your own if you don't wish to buy.

===Buffer/Line Driver IC===
These ICs provide an in-line connection which is buffered via an internal transistor switch to isolate the input from the output. Depending on its type, they can provide conversion between 3.3V logic and 5V logic, as well as the ability to switch the I/O direction.

Example ICs:

74HC245 - 8 line driver, with direction control.

74HC244 - 8 line driver, with 4 channel enable/disable.

ULN2803 - 8 line Transistor Array - Also some will allow switching of high currents, so are suitable for driving motors or other devices.

Example Circuit:

[http://www.thebox.myzen.co.uk/Raspberry/Buffer_Board.html Mike Cook's Raspberry Pi ULN2803 Buffer Board]

===Opto-Isolators===
Opto-Isolators work by using an internal photo-LED and photo-sensitive transistor to transfer a digital signal (the LED is switched on, the transistor senses it and switches the circuit on).

This allows each side of the circuit to be fully isolated from each other, they can even be at different voltage levels if required (this is why they are often used in PSUs). Care must be taken when selecting a suitable IC as many it require a reasonable driving current to drive the internal photo-LED.

Example IC:

ISP621-4X - 4 line (although the RPi may have issues driving this directly due to 10mA input).

Additional Info:

[http://www.arunet.co.uk/tkboyd/ec/ec1optoiso.htm arunet.co.uk - Using Opto-isolators with Microcontrollers]

===I/O Expanders===
An alternative route, it to allow the Raspberry Pi to digitally interface over it's SPI or I2C connections to a purpose built I/O Expander chip. These chips are designed to allow multiple inputs/outputs to be fed to a processor over a few I/O pins (multiple I/O chips can be addressed separately too), they often have multiple high current channels available and can also include analogue to digital converters.

Protection is provided by allowing you to connect a wider range of circuits directly to the I/O Expanders pins, while the Raspberry Pi will send and receive standard logic level signals.

Example IC:

PCA9555

===External Processors===
Much like using the above I/O Expanders, it is possible to interface directly with other microprocessors, for instance the TI LaunchPad or Andrino. Any additional features of the microprocessor will be at your disposal, such as built in ADCs and PWMs, timers or comms interfaces etc.

The external processor will need to be configured so that you can communicate with it, but you can also allow additional processing and control to be handled within the external processor as required. Also care must be taken to ensure suitable logic level conversions are done (3.3V to 5V and back again).

Example IC:

Andrino

MSP430G2553

===Wireless Transceivers===
Similar to using an external processor or I/O expander, normal logic levels can be used between the raspberry pi and the transceiver, clearly if the input/output is not physically connected, then there is good overall protection.

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Tutorial EGHS:GPIO Protection Circuits

2012-07-06T08:43:30Z

Meltwater: /* Protection Circuits */

{{Template:RPi Tutorials}}

''This page is part of a work in progress.''

==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==
In order to protect the Raspberry Pi hardware, it is highly recommended that the GPIO pins are protected in some form to avoid damage. This page will introduce some circuits which can be used to protect the pins.

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

THIS PAGE IS UNDER-CONSTRUCTION AND UNTESTED ON RASPBERRY PI HARDWARE

==Why protect the pins?==
While the GPIO pins can provide lots of useful control and sensing ability to the Raspberry Pi, it is important to remember they are wired directly into the internal core of the system. This means that they provide a very easy way to introduce bad voltages and currents into the delicate heart of the Raspberry Pi (this is not good and means it is easy to break it without exercising a little care).

Things we need to protect:

1) Drawing excess current from the pins (or short-circuiting an output)

2) Driving over-voltage on an input pin (anything above 3.3V should be avoided)

3) Static shocks, from touching pins without suitable grounding (often called ESD - ElectroStatic Discharge, occurs when your clothes etc build up an electrical charge as you move around)

All of these can potentially break your Raspberry Pi, damage the GPIO circuits or weaken it over time (reducing its overall life).

==Physical Pin Protection==
You must remember that the GPIO pin connections ([[RPi Low-level peripherals#General Purpose Input/Output (GPIO) | General Purpose Input/Output (GPIO)]]) also carry 3.3V, 5V and GND on the same 2x13pin header, so care must be taken when connecting and disconnecting wires that you don't accidentally connect these pins (i.e. 5V passed onto the GND or connected to 3.3V is likely to cause problems - if you are lucky the Polyfuse will kick in (can take an hour or so to reset), if you are unlucky you may break something permanently.

There are a number of ways to do this (depending on your requirements), such as using some jumpers (see photo) set to one side, strips of wire insulation (ideal for the NC - non-connection pins) or by using a full ribbon cable connector (like those used on IDE hard drives).

Photos required

==Protection Circuits==
There are many ways to protect the GPIO pins electrically, below explains some of the methods.

In many cases, the selected IC will also have electrical limits of their own (hopefully less restrictive than the Raspberry Pi), so you may end up blowing them instead. However, it is preferable to replace an IC (of less value and greater availability) which has been blown than to break your Raspberry Pi.

Please expand these sections with more information about options available
and why some are better than others.

If you are planning on using some of these circuits, it is recommended you research similar circuits to determine the best configuration for your needs.

===Zener Diode Protection===
This method uses a 3.3V Zener diode to limit the voltage which will be applied to the GPIO pins. By placing the diode between the GPIO pin and Gnd, any voltage applied which is greater than 3.3V will cause the Zener diode to "break down" (allow current to flow) through diode to Gnd (ensuring the voltage that reaches the GPIO is no more than 3.3V. Although there are cases where this protection won't fully save the GPIO from damage, it is highly recommended to protect from common wiring errors.

Example Circuit:

[http://www.thebox.myzen.co.uk/Raspberry/Breakout.html Mike Cook's Raspberry Pi Breakout Board]

===Transistor Switch===
See the second part of the [[RPi Tutorial EGHS:LED output#Circuit 2 - LED Driving Circuit (using Transistor Switching Circuit) | LED Driving Circuit (using Transistor Switching Circuit)]].

===Transistor Logic Shifters===
As well as providing protection, logic shifters will allow you to safely mix circuits which use different logic voltages. For instance many I2C (a common protocol) devices use 5V logic, so a level shifter is required to interface them with the RPi. If you always intend using the level shifter with the RPi, then using Zener diodes as mentioned above, on the low-voltage supply is probably a good idea too.

Other information on Logic level shifters (use only as a guide, particularly regarding the "out-of-specs" section):

[http://arduino.cc/playground/Main/I2CBi-directionalLevelShifter Arduino.cc I2C bi-directional level shifter]

[http://www.nxp.com/documents/application_note/AN10441.pdf NXP's Application Note AN10441 Level shifting techniques in I2C-bus design]

Example Circuit:

[http://www.sparkfun.com/products/8745 Sparkfun's Logic Level Converter] - Product linked only because they also provide schematics so you can make your own if you don't wish to buy.

===Buffer/Line Driver IC===
These ICs provide an in-line connection which is buffered via an internal transistor switch to isolate the input from the output. Depending on its type, they can provide conversion between 3.3V logic and 5V logic, as well as the ability to switch the I/O direction.

Example ICs:

74HC245 - 8 line driver, with direction control.

74HC244 - 8 line driver, with 4 channel enable/disable.

ULN2803 - 8 line Transistor Array - Also some will allow switching of high currents, so are suitable for driving motors or other devices.

Example Circuit:

[http://www.thebox.myzen.co.uk/Raspberry/Buffer_Board.html Mike Cook's Raspberry Pi ULN2803 Buffer Board]

===Opto-Isolators===
Opto-Isolators work by using an internal photo-LED and photo-sensitive transistor to transfer a digital signal (the LED is switched on, the transistor senses it and switches the circuit on).

This allows each side of the circuit to be fully isolated from each other, they can even be at different voltage levels if required (this is why they are often used in PSUs). Care must be taken when selecting a suitable IC as many it require a reasonable driving current to drive the internal photo-LED.

Example IC:

ISP621-4X - 4 line (although the RPi may have issues driving this directly due to 10mA input).

Additional Info:

[http://www.arunet.co.uk/tkboyd/ec/ec1optoiso.htm arunet.co.uk - Using Opto-isolators with Microcontrollers]

===I/O Expanders===
An alternative route, it to allow the Raspberry Pi to digitally interface over it's SPI or I2C connections to a purpose built I/O Expander chip. These chips are designed to allow multiple inputs/outputs to be fed to a processor over a few I/O pins (multiple I/O chips can be addressed separately too), they often have multiple high current channels available and can also include analogue to digital converters.

Protection is provided by allowing you to connect a wider range of circuits directly to the I/O Expanders pins, while the Raspberry Pi will send and receive standard logic level signals.

Example IC:

PCA9555

===External Processors===
Much like using the above I/O Expanders, it is possible to interface directly with other microprocessors, for instance the TI LaunchPad or Andrino. Any additional features of the microprocessor will be at your disposal, such as built in ADCs and PWMs, timers or comms interfaces etc.

The external processor will need to be configured so that you can communicate with it, but you can also allow additional processing and control to be handled within the external processor as required. Also care must be taken to ensure suitable logic level conversions are done (3.3V to 5V and back again).

Example IC:

Andrino

MSP430G2553

===Wireless Transceivers===
Similar to using an external processor or I/O expander, normal logic levels can be used between the raspberry pi and the transceiver, clearly if the input/output is not physically connected, then there is good overall protection.

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Tutorial EGHS:GPIO Protection Circuits

2012-07-06T08:42:10Z

Meltwater: /* Protection Circuits */ - added some more details

{{Template:RPi Tutorials}}

''This page is part of a work in progress.''

==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==
In order to protect the Raspberry Pi hardware, it is highly recommended that the GPIO pins are protected in some form to avoid damage. This page will introduce some circuits which can be used to protect the pins.

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

THIS PAGE IS UNDER-CONSTRUCTION AND UNTESTED ON RASPBERRY PI HARDWARE

==Why protect the pins?==
While the GPIO pins can provide lots of useful control and sensing ability to the Raspberry Pi, it is important to remember they are wired directly into the internal core of the system. This means that they provide a very easy way to introduce bad voltages and currents into the delicate heart of the Raspberry Pi (this is not good and means it is easy to break it without exercising a little care).

Things we need to protect:

1) Drawing excess current from the pins (or short-circuiting an output)

2) Driving over-voltage on an input pin (anything above 3.3V should be avoided)

3) Static shocks, from touching pins without suitable grounding (often called ESD - ElectroStatic Discharge, occurs when your clothes etc build up an electrical charge as you move around)

All of these can potentially break your Raspberry Pi, damage the GPIO circuits or weaken it over time (reducing its overall life).

==Physical Pin Protection==
You must remember that the GPIO pin connections ([[RPi Low-level peripherals#General Purpose Input/Output (GPIO) | General Purpose Input/Output (GPIO)]]) also carry 3.3V, 5V and GND on the same 2x13pin header, so care must be taken when connecting and disconnecting wires that you don't accidentally connect these pins (i.e. 5V passed onto the GND or connected to 3.3V is likely to cause problems - if you are lucky the Polyfuse will kick in (can take an hour or so to reset), if you are unlucky you may break something permanently.

There are a number of ways to do this (depending on your requirements), such as using some jumpers (see photo) set to one side, strips of wire insulation (ideal for the NC - non-connection pins) or by using a full ribbon cable connector (like those used on IDE hard drives).

Photos required

==Protection Circuits==
There are many ways to protect the GPIO pins electrically, below explains some of the methods.

In many cases, the selected IC will also have electrical limits of their own (hopefully less restrictive than the Raspberry Pi), so you may end up blowing them instead. However, it is preferable to replace an IC (of less value and greater availability) which has been blown than to break your Raspberry Pi.

Please expand these sections with more information about options available
and why some are better than others.

===Zener Diode Protection===
This method uses a 3.3V Zener diode to limit the voltage which will be applied to the GPIO pins. By placing the diode between the GPIO pin and Gnd, any voltage applied which is greater than 3.3V will cause the Zener diode to "break down" (allow current to flow) through diode to Gnd (ensuring the voltage that reaches the GPIO is no more than 3.3V. Although there are cases where this protection won't fully save the GPIO from damage, it is highly recommended to protect from common wiring errors.

Example Circuit:

[http://www.thebox.myzen.co.uk/Raspberry/Breakout.html Mike Cook's Raspberry Pi Breakout Board]

===Transistor Switch===
See the second part of the [[RPi Tutorial EGHS:LED output#Circuit 2 - LED Driving Circuit (using Transistor Switching Circuit) | LED Driving Circuit (using Transistor Switching Circuit)]].

===Transistor Logic Shifters===
As well as providing protection, logic shifters will allow you to safely mix circuits which use different logic voltages. For instance many I2C (a common protocol) devices use 5V logic, so a level shifter is required to interface them with the RPi. If you always intend using the level shifter with the RPi, then using Zener diodes as mentioned above, on the low-voltage supply is probably a good idea too.

Other information on Logic level shifters (use only as a guide, particularly regarding the "out-of-specs" section):

[http://arduino.cc/playground/Main/I2CBi-directionalLevelShifter Arduino.cc I2C bi-directional level shifter]

[http://www.nxp.com/documents/application_note/AN10441.pdf NXP's Application Note AN10441 Level shifting techniques in I2C-bus design]

Example Circuit:

[http://www.sparkfun.com/products/8745 Sparkfun's Logic Level Converter] - Product linked only because they also provide schematics so you can make your own if you don't wish to buy.

===Buffer/Line Driver IC===
These ICs provide an in-line connection which is buffered via an internal transistor switch to isolate the input from the output. Depending on its type, they can provide conversion between 3.3V logic and 5V logic, as well as the ability to switch the I/O direction.

Example ICs:

74HC245 - 8 line driver, with direction control.

74HC244 - 8 line driver, with 4 channel enable/disable.

ULN2803 - 8 line Transistor Array - Also some will allow switching of high currents, so are suitable for driving motors or other devices.

Example Circuit:

[http://www.thebox.myzen.co.uk/Raspberry/Buffer_Board.html Mike Cook's Raspberry Pi ULN2803 Buffer Board]

===Opto-Isolators===
Opto-Isolators work by using an internal photo-LED and photo-sensitive transistor to transfer a digital signal (the LED is switched on, the transistor senses it and switches the circuit on).

This allows each side of the circuit to be fully isolated from each other, they can even be at different voltage levels if required (this is why they are often used in PSUs). Care must be taken when selecting a suitable IC as many it require a reasonable driving current to drive the internal photo-LED.

Example IC:

ISP621-4X - 4 line (although the RPi may have issues driving this directly due to 10mA input).

Additional Info:

[http://www.arunet.co.uk/tkboyd/ec/ec1optoiso.htm arunet.co.uk - Using Opto-isolators with Microcontrollers]

===I/O Expanders===
An alternative route, it to allow the Raspberry Pi to digitally interface over it's SPI or I2C connections to a purpose built I/O Expander chip. These chips are designed to allow multiple inputs/outputs to be fed to a processor over a few I/O pins (multiple I/O chips can be addressed separately too), they often have multiple high current channels available and can also include analogue to digital converters.

Protection is provided by allowing you to connect a wider range of circuits directly to the I/O Expanders pins, while the Raspberry Pi will send and receive standard logic level signals.

Example IC:

PCA9555

===External Processors===
Much like using the above I/O Expanders, it is possible to interface directly with other microprocessors, for instance the TI LaunchPad or Andrino. Any additional features of the microprocessor will be at your disposal, such as built in ADCs and PWMs, timers or comms interfaces etc.

The external processor will need to be configured so that you can communicate with it, but you can also allow additional processing and control to be handled within the external processor as required. Also care must be taken to ensure suitable logic level conversions are done (3.3V to 5V and back again).

Example IC:

Andrino

MSP430G2553

===Wireless Transceivers===
Similar to using an external processor or I/O expander, normal logic levels can be used between the raspberry pi and the transceiver, clearly if the input/output is not physically connected, then there is good overall protection.

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Community Magazine

2012-06-28T10:36:39Z

Meltwater: /* Magazine Sites */ - added local links to mags

[[Category:RaspberryPi]]
{{Template:RPi_Learning}}

=About=
The idea/concept for a Community Magazine has been mentioned several times on the forums, and with a lot of community generated quality content available in various places, it seems like such a magazine can be produced (even if it is an electronic or eMagazine equivalent).

==Forum References==
Here are links to some of the discussions about producing such a magazine (some excellent ideas!):

* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine Slice of Pi/MagPi - Raspberry Pi Magazine]
* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine The Pi User - contributor request!]
* [http://www.raspberrypi.org/forum/off-topic/r-pi-magazine-out-now-cough R-Pi magazine out now (cough)]
* [http://www.raspberrypi.org/forum/general-discussion/raspi-magazine-type-publication-website Raspi magazine (/type publication/website)]
* [http://www.raspberrypi.org/forum/off-topic/raspberry-pi-and-programming-in-linux-for-dummies "RASPBERRY PI (and programming in Linux) FOR DUMMIES"]

A "joke" magazine cover!

[http://www.clivebeale.com/stuff/pimag.pdf Example of Raspberry Pi Magazine Concept] (posted by forum user Clive [http://www.clivebeale.com]).

==Magazine Sites==
There are currently a few sites which are aiming to produce a community magazine.

* [http://www.themagpi.com/ The Mag Pi]
Visit the site for the latest issue and live draft of coming issues.
[http://issuu.com/themagpi - Next MagPi Issue Draft - On Issuu.com -]

- Issue 01 - May 2012 - Available NOW -
[http://goo.gl/88l3a The MagPi Issue 1 - May 2012 (elinux.org link)]

- Issue 02 - June 2012 - Available NOW -
[http://goo.gl/l69He The MagPi Issue 2 - June 2012 (elinux.org link)]

* [http://www.thepiuser.co.uk The Pi User]

==Publication Plans/Ideas==
===Idea/Suggestion: On-line Magazine with periodic eMagazine Publication===
Suggested process:

1. Publish the articles on the blog/site etc as and when they are ready (or perhaps at set point spread over the month/quarter depending on content). Budding writers can even proto-type their articles in the wiki if they feel they need input from others before submitting.

2. The site can be set-up to have a home page with a magazine style index front end, where each regular article gets linked etc. Some basic tile type (metro) index could be quite effective (with hopefully not too much work once setup).

3. Articles can be made available though RSS so people can have the latest article delivered when they are available.

4. After each cycle (whatever the period ends up being), the articles are collected and formulated into a magazine format, ideally nice online flippable format [http://issuu.com/] (suggested by Deep Thought), and of course downloadable format (pdf or ebook etc) which people can read on their ereaders or print out (consideration should be given for b/w printing and reading on ereaders too - separate compact version dropping backgrounds or something?). Again this can probably be delivered through RSS and through kindle (depending on how the magazine subscription process works for kindle).

=Get Involved!=
==Donated Content==
If you are blog writer or you already have content which you are happy to be used in the magazine then please add links here (or create suitable wiki page for the content).

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original - including photos etc).

==Article Ideas==
Add to and list any ideas for articles you would like to see and/or write below.

Note: If you want to write the article within the wiki (so you can get help from others)
then feel free to create a wiki page below for your article, use name "RPi Mag xxxx"
with suitable short name.

==Photographers/illustrators and Images==
A key aspect will be to have some quality images to use in the magazine formatting and presentation.

If you are a keen photographer/illustrator then please send us links to any photos (i.e. on Flicker/Photobucket etc) you have which we can freely use for the magazine. Images can be directly related to using the Raspberry Pi, or abstract (useful for backgrounds and providing style), or perhaps directly related to an article you've seen, or would like to see or want to write.

Perhaps we can include a section as a photography competition too.

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original).

==Editors/Graphic Designers==
In order to produce the formatted version of the magazine we will need some skilful people who can make the content look visually appealing, as well as ensuring the content is correct and legible (typos etc).

==References==
<references>
</references>

{{Template:Raspberry Pi}}

File:The MagPi Issue 2 Final.pdf

2012-06-28T10:14:04Z

Meltwater: The_MagPi_Issue_2_Final.pdf www.themagpi.com

The_MagPi_Issue_2_Final.pdf www.themagpi.com

File:The MagPi Issue 1 Final.pdf

2012-06-28T10:09:23Z

Meltwater: The_MagPi_Issue_1_Final.pdf www.themagpi.com

The_MagPi_Issue_1_Final.pdf
www.themagpi.com

RPi Tutorial EGHS:Switch Input

2012-05-16T12:41:03Z

Meltwater: /* Basic Switchx8 Test Module */

{{Template:RPi Tutorials}}

''This page is part of a work in progress.''

==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

==The Hardware==
===Theory===
Work in progess...

The GPIO pin on the RPi when defined as an '''Input''' allows the state of the pin to be read as with HIGH or LOW. This allows us to use a simple switch to set the state of the pin and the software can read this and respond to the change (i.e. change the audio volume output or light an LED wired to another pin).

''For additional theory see'' <ref>[http://www.scriptoriumdesigns.com/embedded/gpio_in.php Introduction To Embedded Programming - GPIO Input]</ref>

====Logic Levels====
For the GPIO pin to determine if an input level is HIGH or LOW it has to detect that the voltage on the pin is above or below a set level, you should aim to set the pin to 10% of the logic voltage (HIGH for the RPi this is 3.3V - so 2.97V to 3.3V, LOW is 0V to 0.33V).

If the pin voltage is somewhere between 2.97V and 0.33V then the system may not reliably determine if a HIGH or LOW value is set (particularly as you get closer to 1.65V (halfway)).

If you drive voltages over 3.3V or negative voltages then you will risk damaging the internal GPIO circuits and perhaps even killing the RPi (which is why using extra components to protect and buffer inputs is recommended).

====PullUp/PullDown====
When a GPIO pin is disconnected and set as an '''input''', the voltage is considered ''floating'' since there is no defined voltage level being applied to the pin. Therefore a good input circuit needs to apply either a HIGH voltage or a LOW voltage.

[[File:EGHS-BadSwitch.jpg|100px|thumb|left|No Pull-Up/Pull-Down]]

The top circuit with '''Switch 1''' (Double-poll switch) is fine, however, when using other types of switches, such as '''Switch 2''' (i.e. Single-poll switch) you will create a short-circuit when the switch is pressed!

[[File:EGHS-PullUpDownSwitch.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit]]

However, by simply using a resistor in-between the short-circuit can be avoided. The value of the resistor is determined by the '''leakage''' current of the GPIO pin (the current used by the circuit to read the pin) (although this is not specified for the RPi, it is expected to be in the range of 1uA) and the amount of voltage drop it creates as a result.

If we set R1 to 10kohms, and max drop from Vcc is 10% (0.33V).
Max leakage current = Vdrop/R1
= 0.33/10000
= 33uA

By picking a large resistor it ensures less current is drawn by the circuit, when the switch is active (this is why a large value of 10Kohms is usually used).

Current drawn = Vcc/R1
= 3.3/10000
= 0.33mA

The above circuit shows '''Switch 1''' which when pressed will provide a '''LOW''' signal to the GPIO pin (otherwise the resistor pulls the circuit '''UP HIGH'''), and '''Switch 2''' which when pressed will provide a '''HIGH''' signal to the GPIO pin (otherwise the resistor pulls the circuit '''DOWN LOW''').

''This is covered in a lot more detail here (although note the logic level here is 5V!) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino inputs]</ref>.''

One additional thing to note is that the RPi GPIO has internal Pull-Up and Pull-Down resistors which can be enabled through software registers<ref>[http://dmkenr5gtnd8f.cloudfront.net/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf BCM2835 ARM Peripherals Datasheet]</ref>.

This means that you can avoid the extra circuit above and simply place a switching between Vcc or GND, but you have to set the Pull-Up/Pull-Down registers for it to function correctly. To keep the software simple and to avoid any damage, it is recommended you start with using external Pull-Ups and Pull-Downs until you are confident setting these registers correctly.

====Output Protection====
An extra consideration for safer input design, is to consider the case when the software incorrectly drives the GPIO pin as an output rather than using as an input.

Now, in the second circuit, when Switch 2 is activated, the GPIO pin is connected directly to Vcc (3.3V), if the software is trying to drive this pin '''LOW''' (similarly when the opposite is happening switch connects to GND and the software is driving the pin '''HIGH'''). This could damage the circuit by drawing/supplying more current through the GPIO pin than it can handle.

By putting another resistor on the GPIO pin, any short-circuit HIGH or LOW will have the current limited.
[[File:EGHS-PullUpDownSwitchProtected.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit with Output Short-circuit Protection]]

By picking 1Kohmn resistor for R2, the maximum current will be:

Imax = V/R
= 3.3/1000
= 3.3mA (which should be within safe limits)

''A little more detail is given here (again note, logic level and supply are 5V!) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino Tutorial - Arduino inputs]</ref>''

====De-bouncing Hardware verses Software====
The last consideration is whether hardware de-bouncing is required. Basically any manual switch will not cleanly make or break a connection when you switch it, and is likely to trigger any input value multiple times (as the contacts move momentarily from one state to another).

This can be dealt with by applying a simple filter in the circuit (achieved by putting a capacitor in parallel with the switch). The capacitor acts like a smoothing filter (energy from fast transitions of voltage is temporarily stored and released by the capacitor), this slows the change from LOW to HIGH and vice-a-versa.

[[File:EGHS-PullUpDownSwitchProtectedDebounced.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit with Output Short-circuit Protection, with De-bouncing]]

''A good explanation (with graphs) is shown here (see Hardware Interfacing section at the bottom) <ref>[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_PushButton MSP430 LaunchPad PushButton]</ref>''

While hardware de-bouncing or smoothing of this input is often quite helpful, the problem occurs if you require very fast switching or response times, since the capacitor now delays any possible detection of the switch. However, if de-bouncing is handled within the software (simplest method is to re-read the state after a short delay) it can be fine tuned to meet your needs.

''A little more detail is given here (in Brooklyn Debounce section) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino Tutorial - Arduino inputs]</ref>''

===Basic Switchx8 Test Module===
[[File:EGHS-SWx8ModuleCircuit.jpg|300px|left|thumb|The Basic Switchx8 Test Module Circuit (only 4 of the 8 switches are shown)]]
The Basic Switchx8 Test Module Test module has been built to allow easy testing of GPIO inputs by connecting up to 8 switches, in a number of configurations.

Resistor values:
R1 = 11Kohms (Green)
R2 = 1Kohms (Blue)

The slightly unusual layout is down to using up some spare veroboard, so it could probably be designed better (but it works well enough for my needs).

Also, to allow flexibility, removable connections are put in between R1 and the switches.

Expected normal use:
* 3.3V is applied to either of the two pins on the far right.
* Gnd is applied to either of the two pins on the buttom (next to the switch bank).
* GPIO Output is taken from the top row of pins.
* This particular switch bank the switch is open when down (providing a set value on the output).

The module allows a number of circuit configurations if required:
# The protection resistors (R2) can be removed by connecting the GPIO directly to the middle pins.
# The pull up/down resistors (R1) can be removed (so internal pull up/downs can be used on their own).
# The circuit can be switched from active HIGH to active LOW by swapping the power connections (by connecting Vcc to the pins near the switch bank and Gnd to the right-side pins, the switch ON = HIGH output. Alternatively the other way around, with Gnd by the switch bank and Vcc on the right, the switch ON = LOW output).
# A second bank of pins could be added in the middle, to allow the protection resistors (R2) to be removed while still using the Pull Up/Down resistors (R1), if required.

Basic Switchx8 Test Module (Control pins at top, GND/PWR connection at bottom-right and middle-right, removable connections in the middle for connecting pull up/down resistors).
[[File:EGHS-SWx8Module.jpg|300px|thumb|left|Basic Switchx8 Test Module]][[File:EGHS-SWx8ModulePCB.jpg|300px|thumb|centre|Circuit with track breaks marked in red]]

==The Software==
While the RPi is not available, I can only confirm the TI LaunchPad code works for me.
===TI LaunchPad===
The specifics and background behind the code is detailed very well on the following sites:

[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_PushButton MSP430 LaunchPad PushButton]

[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_Interrupt_vs_Polling MSP430 LaunchPad Interrupt vs Polling]

Sample test code for single switch input (tested on TI MSP430G2553 device).
Reads in switch input from Port 1.3, and lights LED output on Port 1.0 (can be used with or without external circuit connected - uses default pins for SW2 and LED1).

Code:
* [http://www.pastebucket.com/1913 main.c] - Main calling functions (includes pin setup and switch between POLLING/INTERRUPT)

===RPi===
No input test code available yet.

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Tutorial EGHS:Switch Input

2012-05-16T12:40:33Z

Meltwater: /* Basic Switchx8 Test Module */

{{Template:RPi Tutorials}}

''This page is part of a work in progress.''

==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

==The Hardware==
===Theory===
Work in progess...

The GPIO pin on the RPi when defined as an '''Input''' allows the state of the pin to be read as with HIGH or LOW. This allows us to use a simple switch to set the state of the pin and the software can read this and respond to the change (i.e. change the audio volume output or light an LED wired to another pin).

''For additional theory see'' <ref>[http://www.scriptoriumdesigns.com/embedded/gpio_in.php Introduction To Embedded Programming - GPIO Input]</ref>

====Logic Levels====
For the GPIO pin to determine if an input level is HIGH or LOW it has to detect that the voltage on the pin is above or below a set level, you should aim to set the pin to 10% of the logic voltage (HIGH for the RPi this is 3.3V - so 2.97V to 3.3V, LOW is 0V to 0.33V).

If the pin voltage is somewhere between 2.97V and 0.33V then the system may not reliably determine if a HIGH or LOW value is set (particularly as you get closer to 1.65V (halfway)).

If you drive voltages over 3.3V or negative voltages then you will risk damaging the internal GPIO circuits and perhaps even killing the RPi (which is why using extra components to protect and buffer inputs is recommended).

====PullUp/PullDown====
When a GPIO pin is disconnected and set as an '''input''', the voltage is considered ''floating'' since there is no defined voltage level being applied to the pin. Therefore a good input circuit needs to apply either a HIGH voltage or a LOW voltage.

[[File:EGHS-BadSwitch.jpg|100px|thumb|left|No Pull-Up/Pull-Down]]

The top circuit with '''Switch 1''' (Double-poll switch) is fine, however, when using other types of switches, such as '''Switch 2''' (i.e. Single-poll switch) you will create a short-circuit when the switch is pressed!

[[File:EGHS-PullUpDownSwitch.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit]]

However, by simply using a resistor in-between the short-circuit can be avoided. The value of the resistor is determined by the '''leakage''' current of the GPIO pin (the current used by the circuit to read the pin) (although this is not specified for the RPi, it is expected to be in the range of 1uA) and the amount of voltage drop it creates as a result.

If we set R1 to 10kohms, and max drop from Vcc is 10% (0.33V).
Max leakage current = Vdrop/R1
= 0.33/10000
= 33uA

By picking a large resistor it ensures less current is drawn by the circuit, when the switch is active (this is why a large value of 10Kohms is usually used).

Current drawn = Vcc/R1
= 3.3/10000
= 0.33mA

The above circuit shows '''Switch 1''' which when pressed will provide a '''LOW''' signal to the GPIO pin (otherwise the resistor pulls the circuit '''UP HIGH'''), and '''Switch 2''' which when pressed will provide a '''HIGH''' signal to the GPIO pin (otherwise the resistor pulls the circuit '''DOWN LOW''').

''This is covered in a lot more detail here (although note the logic level here is 5V!) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino inputs]</ref>.''

One additional thing to note is that the RPi GPIO has internal Pull-Up and Pull-Down resistors which can be enabled through software registers<ref>[http://dmkenr5gtnd8f.cloudfront.net/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf BCM2835 ARM Peripherals Datasheet]</ref>.

This means that you can avoid the extra circuit above and simply place a switching between Vcc or GND, but you have to set the Pull-Up/Pull-Down registers for it to function correctly. To keep the software simple and to avoid any damage, it is recommended you start with using external Pull-Ups and Pull-Downs until you are confident setting these registers correctly.

====Output Protection====
An extra consideration for safer input design, is to consider the case when the software incorrectly drives the GPIO pin as an output rather than using as an input.

Now, in the second circuit, when Switch 2 is activated, the GPIO pin is connected directly to Vcc (3.3V), if the software is trying to drive this pin '''LOW''' (similarly when the opposite is happening switch connects to GND and the software is driving the pin '''HIGH'''). This could damage the circuit by drawing/supplying more current through the GPIO pin than it can handle.

By putting another resistor on the GPIO pin, any short-circuit HIGH or LOW will have the current limited.
[[File:EGHS-PullUpDownSwitchProtected.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit with Output Short-circuit Protection]]

By picking 1Kohmn resistor for R2, the maximum current will be:

Imax = V/R
= 3.3/1000
= 3.3mA (which should be within safe limits)

''A little more detail is given here (again note, logic level and supply are 5V!) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino Tutorial - Arduino inputs]</ref>''

====De-bouncing Hardware verses Software====
The last consideration is whether hardware de-bouncing is required. Basically any manual switch will not cleanly make or break a connection when you switch it, and is likely to trigger any input value multiple times (as the contacts move momentarily from one state to another).

This can be dealt with by applying a simple filter in the circuit (achieved by putting a capacitor in parallel with the switch). The capacitor acts like a smoothing filter (energy from fast transitions of voltage is temporarily stored and released by the capacitor), this slows the change from LOW to HIGH and vice-a-versa.

[[File:EGHS-PullUpDownSwitchProtectedDebounced.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit with Output Short-circuit Protection, with De-bouncing]]

''A good explanation (with graphs) is shown here (see Hardware Interfacing section at the bottom) <ref>[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_PushButton MSP430 LaunchPad PushButton]</ref>''

While hardware de-bouncing or smoothing of this input is often quite helpful, the problem occurs if you require very fast switching or response times, since the capacitor now delays any possible detection of the switch. However, if de-bouncing is handled within the software (simplest method is to re-read the state after a short delay) it can be fine tuned to meet your needs.

''A little more detail is given here (in Brooklyn Debounce section) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino Tutorial - Arduino inputs]</ref>''

===Basic Switchx8 Test Module===
[[File:EGHS-SWx8ModuleCircuit.jpg|300px|left|thumb|The Basic Switchx8 Test Module Circuit (only 4 of the 8 switches are shown)]]
The Basic Switchx8 Test Module Test module has been built to allow easy testing of GPIO inputs by connecting up to 8 switches, in a number of configurations.

Resistor values:
R1 = 11Kohms (Green)
R2 = 1Kohms (Blue)

The slightly unusual layout is down to using up some spare veroboard, so it could probably be designed better (but it works well enough for my needs).

Also, to allow flexibility, removable connections are put in between R1 and the switches.

Expected normal use:
* 3.3V is applied to either of the two pins on the far right.
* Gnd is applied to either of the two pins on the buttom (next to the switch bank).
* GPIO Output is taken from the top row of pins.
* This particular switch bank the switch is open when down (providing a set value on the output).

The module allows a number of circuit configurations if required:
# The protection resistors (R2) can be removed by connecting the GPIO directly to the middle pins.
# The pull up/down resistors (R1) can be removed (so internal pull up/downs can be used on their own).
# The circuit can be switched from active HIGH to active LOW by swapping the power connections (by connecting Vcc to the pins near the switch bank and Gnd to the right-side pins, the switch ON = HIGH output. Alternatively the other way around, with Gnd by the switch bank and Vcc on the right, the switch ON = LOW output).
# A second bank of pins could be added in the middle, to allow the protection resistors (R2) to be removed while still using the Pull Up/Down resistors (R1), if required.

Basic Switchx8 Test Module (Control pins at top, GND/PWR connection at bottom-right and middle-right, removable connections in the middle for connecting pull up/down resistors).
[[File:EGHS-SWx8Module.jpg|300px|thumb|left|Basic Switchx8 Test Module]][[File:EGHS-SWx8ModulePCB.jpg|300px|thumb|centre|Circuit with track breaks marked in red]]

==The Software==
While the RPi is not available, I can only confirm the TI LaunchPad code works for me.
===TI LaunchPad===
The specifics and background behind the code is detailed very well on the following sites:

[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_PushButton MSP430 LaunchPad PushButton]

[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_Interrupt_vs_Polling MSP430 LaunchPad Interrupt vs Polling]

Sample test code for single switch input (tested on TI MSP430G2553 device).
Reads in switch input from Port 1.3, and lights LED output on Port 1.0 (can be used with or without external circuit connected - uses default pins for SW2 and LED1).

Code:
* [http://www.pastebucket.com/1913 main.c] - Main calling functions (includes pin setup and switch between POLLING/INTERRUPT)

===RPi===
No input test code available yet.

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Tutorial EGHS:Switch Input

2012-05-16T12:17:43Z

Meltwater: /* Basic Switchx8 Test Module */ - correct R1 & R2

{{Template:RPi Tutorials}}

''This page is part of a work in progress.''

==Warnings==
While most of these circuits may interface directly to the RPi, the use of a buffered interface (such as the one supplied by the [[RPi Gertboard | Gertboard]]) is recommended which will help protect against damage. Alternatively, experiment with one of the [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]].

'''Extreme caution should be exercised when interfacing hardware at a low level, you may damage your RPi, your equipment and potentially yourself and others. Doing so is at your own risk!'''

==Aims==

Note:
Until RPi devices are available, I can not confirm this will work on a real RPi.
For now, I shall be using the TI LaunchPad (see [[RPi Tutorial Easy GPIO Hardware & Software#Alternative Test Platforms | Alternative Test Platforms]]
for details) to test the hardware on (as it is cheap and the logic levels similar).

==The Hardware==
===Theory===
Work in progess...

The GPIO pin on the RPi when defined as an '''Input''' allows the state of the pin to be read as with HIGH or LOW. This allows us to use a simple switch to set the state of the pin and the software can read this and respond to the change (i.e. change the audio volume output or light an LED wired to another pin).

''For additional theory see'' <ref>[http://www.scriptoriumdesigns.com/embedded/gpio_in.php Introduction To Embedded Programming - GPIO Input]</ref>

====Logic Levels====
For the GPIO pin to determine if an input level is HIGH or LOW it has to detect that the voltage on the pin is above or below a set level, you should aim to set the pin to 10% of the logic voltage (HIGH for the RPi this is 3.3V - so 2.97V to 3.3V, LOW is 0V to 0.33V).

If the pin voltage is somewhere between 2.97V and 0.33V then the system may not reliably determine if a HIGH or LOW value is set (particularly as you get closer to 1.65V (halfway)).

If you drive voltages over 3.3V or negative voltages then you will risk damaging the internal GPIO circuits and perhaps even killing the RPi (which is why using extra components to protect and buffer inputs is recommended).

====PullUp/PullDown====
When a GPIO pin is disconnected and set as an '''input''', the voltage is considered ''floating'' since there is no defined voltage level being applied to the pin. Therefore a good input circuit needs to apply either a HIGH voltage or a LOW voltage.

[[File:EGHS-BadSwitch.jpg|100px|thumb|left|No Pull-Up/Pull-Down]]

The top circuit with '''Switch 1''' (Double-poll switch) is fine, however, when using other types of switches, such as '''Switch 2''' (i.e. Single-poll switch) you will create a short-circuit when the switch is pressed!

[[File:EGHS-PullUpDownSwitch.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit]]

However, by simply using a resistor in-between the short-circuit can be avoided. The value of the resistor is determined by the '''leakage''' current of the GPIO pin (the current used by the circuit to read the pin) (although this is not specified for the RPi, it is expected to be in the range of 1uA) and the amount of voltage drop it creates as a result.

If we set R1 to 10kohms, and max drop from Vcc is 10% (0.33V).
Max leakage current = Vdrop/R1
= 0.33/10000
= 33uA

By picking a large resistor it ensures less current is drawn by the circuit, when the switch is active (this is why a large value of 10Kohms is usually used).

Current drawn = Vcc/R1
= 3.3/10000
= 0.33mA

The above circuit shows '''Switch 1''' which when pressed will provide a '''LOW''' signal to the GPIO pin (otherwise the resistor pulls the circuit '''UP HIGH'''), and '''Switch 2''' which when pressed will provide a '''HIGH''' signal to the GPIO pin (otherwise the resistor pulls the circuit '''DOWN LOW''').

''This is covered in a lot more detail here (although note the logic level here is 5V!) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino inputs]</ref>.''

One additional thing to note is that the RPi GPIO has internal Pull-Up and Pull-Down resistors which can be enabled through software registers<ref>[http://dmkenr5gtnd8f.cloudfront.net/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf BCM2835 ARM Peripherals Datasheet]</ref>.

This means that you can avoid the extra circuit above and simply place a switching between Vcc or GND, but you have to set the Pull-Up/Pull-Down registers for it to function correctly. To keep the software simple and to avoid any damage, it is recommended you start with using external Pull-Ups and Pull-Downs until you are confident setting these registers correctly.

====Output Protection====
An extra consideration for safer input design, is to consider the case when the software incorrectly drives the GPIO pin as an output rather than using as an input.

Now, in the second circuit, when Switch 2 is activated, the GPIO pin is connected directly to Vcc (3.3V), if the software is trying to drive this pin '''LOW''' (similarly when the opposite is happening switch connects to GND and the software is driving the pin '''HIGH'''). This could damage the circuit by drawing/supplying more current through the GPIO pin than it can handle.

By putting another resistor on the GPIO pin, any short-circuit HIGH or LOW will have the current limited.
[[File:EGHS-PullUpDownSwitchProtected.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit with Output Short-circuit Protection]]

By picking 1Kohmn resistor for R2, the maximum current will be:

Imax = V/R
= 3.3/1000
= 3.3mA (which should be within safe limits)

''A little more detail is given here (again note, logic level and supply are 5V!) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino Tutorial - Arduino inputs]</ref>''

====De-bouncing Hardware verses Software====
The last consideration is whether hardware de-bouncing is required. Basically any manual switch will not cleanly make or break a connection when you switch it, and is likely to trigger any input value multiple times (as the contacts move momentarily from one state to another).

This can be dealt with by applying a simple filter in the circuit (achieved by putting a capacitor in parallel with the switch). The capacitor acts like a smoothing filter (energy from fast transitions of voltage is temporarily stored and released by the capacitor), this slows the change from LOW to HIGH and vice-a-versa.

[[File:EGHS-PullUpDownSwitchProtectedDebounced.jpg|100px|thumb|left|Example Pull-Up and Pull-Down Circuit with Output Short-circuit Protection, with De-bouncing]]

''A good explanation (with graphs) is shown here (see Hardware Interfacing section at the bottom) <ref>[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_PushButton MSP430 LaunchPad PushButton]</ref>''

While hardware de-bouncing or smoothing of this input is often quite helpful, the problem occurs if you require very fast switching or response times, since the capacitor now delays any possible detection of the switch. However, if de-bouncing is handled within the software (simplest method is to re-read the state after a short delay) it can be fine tuned to meet your needs.

''A little more detail is given here (in Brooklyn Debounce section) <ref>[http://www.ladyada.net/learn/arduino/lesson5.html Arduino Tutorial - Arduino inputs]</ref>''

===Basic Switchx8 Test Module===
[[File:EGHS-SWx8ModuleCircuit.jpg|300px|left|thumb|The Basic Switchx8 Test Module Circuit (only 4 of the 8 switches are shown)]]
The Basic Switchx8 Test Module Test module has been built to allow easy testing of GPIO inputs by connecting up to 8 switches, in a number of configurations.

Resistor values:
R1 = 11Kohms (Green)
R2 = 1Kohms (Blue)

The slightly unusual layout is down to using up some spare veroboard, so it could probably be designed better (but it works well enough for my needs).

Also, to allow flexibility, removable connections are put in between R1 and the switches.

The module allows a number of circuit configurations if required:
# The protection resistors (R2) can be removed by connecting the GPIO directly to the middle pins.
# The pull up/down resistors (R1) can be removed (so internal pull up/downs can be used on their own).
# The circuit can be switched from active HIGH to active LOW by swapping the power connections (by connecting Vcc to the pins near the switch bank and Gnd to the right-side pins, the switch ON = HIGH output. Alternatively the other way around, with Gnd by the switch bank and Vcc on the right, the switch ON = LOW output).
# A second bank of pins could be added in the middle, to allow the protection resistors (R2) to be removed while still using the Pull Up/Down resistors (R1), if required.

Basic Switchx8 Test Module (Control pins at top, GND/PWR connection at bottom-right and middle-right, removable connections in the middle for connecting pull up/down resistors).
[[File:EGHS-SWx8Module.jpg|300px|thumb|left|Basic Switchx8 Test Module]][[File:EGHS-SWx8ModulePCB.jpg|300px|thumb|centre|Circuit with track breaks marked in red]]

==The Software==
While the RPi is not available, I can only confirm the TI LaunchPad code works for me.
===TI LaunchPad===
The specifics and background behind the code is detailed very well on the following sites:

[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_PushButton MSP430 LaunchPad PushButton]

[http://processors.wiki.ti.com/index.php/MSP430_LaunchPad_Interrupt_vs_Polling MSP430 LaunchPad Interrupt vs Polling]

Sample test code for single switch input (tested on TI MSP430G2553 device).
Reads in switch input from Port 1.3, and lights LED output on Port 1.0 (can be used with or without external circuit connected - uses default pins for SW2 and LED1).

Code:
* [http://www.pastebucket.com/1913 main.c] - Main calling functions (includes pin setup and switch between POLLING/INTERRUPT)

===RPi===
No input test code available yet.

==References==
<references/>

{{Template:Raspberry Pi}}

RPi Community Magazine

2012-05-03T12:19:26Z

Meltwater: /* Magazine Sites */

[[Category:RaspberryPi]]
{{Template:RPi_Learning}}

=About=
The idea/concept for a Community Magazine has been mentioned several times on the forums, and with a lot of community generated quality content available in various places, it seems like such a magazine can be produced (even if it is an electronic or eMagazine equivalent).

==Forum References==
Here are links to some of the discussions about producing such a magazine (some excellent ideas!):

* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine Slice of Pi/MagPi - Raspberry Pi Magazine]
* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine The Pi User - contributor request!]
* [http://www.raspberrypi.org/forum/off-topic/r-pi-magazine-out-now-cough R-Pi magazine out now (cough)]
* [http://www.raspberrypi.org/forum/general-discussion/raspi-magazine-type-publication-website Raspi magazine (/type publication/website)]
* [http://www.raspberrypi.org/forum/off-topic/raspberry-pi-and-programming-in-linux-for-dummies "RASPBERRY PI (and programming in Linux) FOR DUMMIES"]

A "joke" magazine cover!

[http://www.clivebeale.com/stuff/pimag.pdf Example of Raspberry Pi Magazine Concept] (posted by forum user Clive [http://www.clivebeale.com]).

==Magazine Sites==
There are currently a few sites which are aiming to produce a community magazine.

* [http://www.themagpi.com/ The Mag Pi] ([http://themagpi.wordpress.com/ non-flash site])

- Issue 01 - May 2012 - Available NOW -

* [http://www.thepiuser.co.uk The Pi User]

==Publication Plans/Ideas==
===Idea/Suggestion: On-line Magazine with periodic eMagazine Publication===
Suggested process:

1. Publish the articles on the blog/site etc as and when they are ready (or perhaps at set point spread over the month/quarter depending on content). Budding writers can even proto-type their articles in the wiki if they feel they need input from others before submitting.

2. The site can be set-up to have a home page with a magazine style index front end, where each regular article gets linked etc. Some basic tile type (metro) index could be quite effective (with hopefully not too much work once setup).

3. Articles can be made available though RSS so people can have the latest article delivered when they are available.

4. After each cycle (whatever the period ends up being), the articles are collected and formulated into a magazine format, ideally nice online flippable format [http://issuu.com/] (suggested by Deep Thought), and of course downloadable format (pdf or ebook etc) which people can read on their ereaders or print out (consideration should be given for b/w printing and reading on ereaders too - separate compact version dropping backgrounds or something?). Again this can probably be delivered through RSS and through kindle (depending on how the magazine subscription process works for kindle).

=Get Involved!=
==Donated Content==
If you are blog writer or you already have content which you are happy to be used in the magazine then please add links here (or create suitable wiki page for the content).

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original - including photos etc).

==Article Ideas==
Add to and list any ideas for articles you would like to see and/or write below.

Note: If you want to write the article within the wiki (so you can get help from others)
then feel free to create a wiki page below for your article, use name "RPi Mag xxxx"
with suitable short name.

==Photographers/illustrators and Images==
A key aspect will be to have some quality images to use in the magazine formatting and presentation.

If you are a keen photographer/illustrator then please send us links to any photos (i.e. on Flicker/Photobucket etc) you have which we can freely use for the magazine. Images can be directly related to using the Raspberry Pi, or abstract (useful for backgrounds and providing style), or perhaps directly related to an article you've seen, or would like to see or want to write.

Perhaps we can include a section as a photography competition too.

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original).

==Editors/Graphic Designers==
In order to produce the formatted version of the magazine we will need some skilful people who can make the content look visually appealing, as well as ensuring the content is correct and legible (typos etc).

==References==
<references>
</references>

{{Template:Raspberry Pi}}

RPi Community

2012-05-03T12:15:24Z

Meltwater: /* Raspberry Pi Community e-Magazine */

[[Category:RaspberryPi]]
{{Template:RPi_Learning}}

==About==

The Raspberry Pi Community is steadily growing, so get involved where-ever you want to and share.

'''Please do add links to any Raspberry Pi related forums/subforums/blog pages which focus on the RPi.'''

'''The more the community can connect with one another the better it will be.'''

== Download Mirrors==
Please add a link if you mirror official foundation download images. Please also remove the link when it's no longer available.

[[RPi Download Mirrors]]

== Raspberry Pi Community e-Magazine ==

[http://www.themagpi.com/ The Mag Pi] ([http://themagpi.wordpress.com/ non-flash site])

- Issue 01 - May 2012 - Available NOW -

[http://www.thepiuser.co.uk The Pi User]

Get involved!

Contribute and be part of the [[RPi Community Magazine]] - contact the site and join in.

==Forums==
*[http://www.raspberrypi.org/forum Official Raspberry Pi Forum] - A great place to share ideas and get the latest information on the Raspberry Pi.

*[http://www.raspberrymod.com/ Raspberrymod.com] - Boost your device, share ideas and knowledge, ask for help and find useful how to's.

*[http://www.raspberrypiforums.com/ RaspberryPiForums.com] - - New Community forum intended to provide Guides and Tutorials for Raspberry Pi Users, and space for users to work on more complex projects.

*[http://www.frambozenbier.org/index.php/raspi-forum Frambozenbier (Raspberry Pi Homebrew)] - These forums are intended to provide practical information about Building, Developing and Sharing information about the Raspberry Pi, in addition to the more "general discussions" that go on in official forums.

*[http://www.edugeek.net/forums/frambozenbier-raspi-forums/ RasPi Forums on EduGeek.net] - Edugeek is a site for Educational network and ICT admins. This is the dedicated Raspberry Pi sections.

*[http://amateurradiopi.org/forum AmateurRadioPi.org Forums] - A forum centered around discussing the interactions between Amateur (HAM) Radio and the Raspberry Pi.

*[http://www.worldofpi.com/ World Of Pi] A forum based on all things Raspberry Pi ranging from basic usage through to programming and electronics/robotics.

==Blogs/News==
* [http://russelldavis.org/ Russell Davis' Blog] - Russell Davis (aka forum admin ukscone) includes posts about the story of the Raspberry Pi, general RPi stuff and other non-Rpi posts too.

* [http://www.pyrosoft.co.uk/blog/ Pyrosoft Paul Maunders' Blog] - Paul Maunders, owner of beta board #8<ref>http://www.pyrosoft.co.uk/blog/2012/01/13/raspberry-pi-8-first-photoshoot/</ref>, provides details about the new board and its use.

* [http://blogs.arcsoftwareconsultancy.com/pi/ Arc Software Consultancy using the Raspberry Pi Blog] - Blogging the experiences of the Arc Software team as they learn about, experiment with and develop software for the Raspberry Pi computer.

* [http://www.raspberrypiblog.com/ Unofficial RPi blog by a software developer]

* [http://raspberrypiblog.ics.com/ ICS Raspberry Pi blog]

* [http://www.cnx-software.com/tag/raspberry-pi/ CNXSoft Blog Raspberry Pi] - Blog posts about the Raspberry Pi including news and how-tos.

* [http://www.raspberryprojects.com/ RaspberryProjects.com] - mutli user blogging for all projects.

* [http://amateurradiopi.org/ AmateurRadioPi.org] - A blog for documenting interactions between amateur radio and the Raspberry Pi.

== Distributions & Development Groups ==
The RPi without an operating system and software to run on it. Many of the groups involved have RPi specific sections and groups working on RPi specific releases and projects.

*[http://wiki.qt-project.org/Qt_RaspberryPi Qt on Raspberry Pi]
The goal of this project is to develop the required enablers for App and Platform Developers to enjoy Qt 5 after investing $35 in a Raspberry Pi board.

''See the [[RaspberryPiBoardDistributions | RPi Distributions]] page for details about the various groups and links to places where you can get involved with building and using RPi Operating Systems.''

''See the [[RPi Programming | RPi Programming]] page for details about the different programming languages and groups which are focusing on them.''

== Other Groups ==

* [https://www.facebook.com/pages/Raspberry-Pi/203296286406503?sk=wall Facebook ]
* [http://www.linkedin.com/groups?about=&gid=4232349 LinkedIn ]
* [https://plus.google.com/107182636490355951240/posts Google Plus]

== Other Pages ==

*[[RPi Education | Educational links]]
*[http://www.raspberrypi.org/forum/general-discussion/conferences-and-other-public-appearances Conferences] (R.Pi Forum thread)
*[http://www.raspberrypprojects.com Raspberry Projects] Multi-User blog site for plans/projects
*[http://www.raspberrypidownload.co.uk RaspberryPi Download] Dedicated Raspberry Pi Mirror
*[https://rpi-developers.com/ RaspberryPi Developers] Independent Forge site for RaspberryPi projects and development.
*[https://www.openindieproject.org Open Indie Project Dot Org] Non-profit organisation developing Open Source projects for use with the RaspberryPi

==References==
<references>
</references>

{{Template:Raspberry Pi}}

RPi Community

2012-05-03T12:14:53Z

Meltwater: /* Raspberry Pi Community e-Magazine */

[[Category:RaspberryPi]]
{{Template:RPi_Learning}}

==About==

The Raspberry Pi Community is steadily growing, so get involved where-ever you want to and share.

'''Please do add links to any Raspberry Pi related forums/subforums/blog pages which focus on the RPi.'''

'''The more the community can connect with one another the better it will be.'''

== Download Mirrors==
Please add a link if you mirror official foundation download images. Please also remove the link when it's no longer available.

[[RPi Download Mirrors]]

== Raspberry Pi Community e-Magazine ==

[http://www.themagpi.com/ The Mag Pi] ([http://themagpi.wordpress.com/ non-flash site])

- Issue 01 May Released -

[http://www.thepiuser.co.uk The Pi User]

Get involved!

Contribute and be part of the [[RPi Community Magazine]] - contact the site and join in.

==Forums==
*[http://www.raspberrypi.org/forum Official Raspberry Pi Forum] - A great place to share ideas and get the latest information on the Raspberry Pi.

*[http://www.raspberrymod.com/ Raspberrymod.com] - Boost your device, share ideas and knowledge, ask for help and find useful how to's.

*[http://www.raspberrypiforums.com/ RaspberryPiForums.com] - - New Community forum intended to provide Guides and Tutorials for Raspberry Pi Users, and space for users to work on more complex projects.

*[http://www.frambozenbier.org/index.php/raspi-forum Frambozenbier (Raspberry Pi Homebrew)] - These forums are intended to provide practical information about Building, Developing and Sharing information about the Raspberry Pi, in addition to the more "general discussions" that go on in official forums.

*[http://www.edugeek.net/forums/frambozenbier-raspi-forums/ RasPi Forums on EduGeek.net] - Edugeek is a site for Educational network and ICT admins. This is the dedicated Raspberry Pi sections.

*[http://amateurradiopi.org/forum AmateurRadioPi.org Forums] - A forum centered around discussing the interactions between Amateur (HAM) Radio and the Raspberry Pi.

*[http://www.worldofpi.com/ World Of Pi] A forum based on all things Raspberry Pi ranging from basic usage through to programming and electronics/robotics.

==Blogs/News==
* [http://russelldavis.org/ Russell Davis' Blog] - Russell Davis (aka forum admin ukscone) includes posts about the story of the Raspberry Pi, general RPi stuff and other non-Rpi posts too.

* [http://www.pyrosoft.co.uk/blog/ Pyrosoft Paul Maunders' Blog] - Paul Maunders, owner of beta board #8<ref>http://www.pyrosoft.co.uk/blog/2012/01/13/raspberry-pi-8-first-photoshoot/</ref>, provides details about the new board and its use.

* [http://blogs.arcsoftwareconsultancy.com/pi/ Arc Software Consultancy using the Raspberry Pi Blog] - Blogging the experiences of the Arc Software team as they learn about, experiment with and develop software for the Raspberry Pi computer.

* [http://www.raspberrypiblog.com/ Unofficial RPi blog by a software developer]

* [http://raspberrypiblog.ics.com/ ICS Raspberry Pi blog]

* [http://www.cnx-software.com/tag/raspberry-pi/ CNXSoft Blog Raspberry Pi] - Blog posts about the Raspberry Pi including news and how-tos.

* [http://www.raspberryprojects.com/ RaspberryProjects.com] - mutli user blogging for all projects.

* [http://amateurradiopi.org/ AmateurRadioPi.org] - A blog for documenting interactions between amateur radio and the Raspberry Pi.

== Distributions & Development Groups ==
The RPi without an operating system and software to run on it. Many of the groups involved have RPi specific sections and groups working on RPi specific releases and projects.

*[http://wiki.qt-project.org/Qt_RaspberryPi Qt on Raspberry Pi]
The goal of this project is to develop the required enablers for App and Platform Developers to enjoy Qt 5 after investing $35 in a Raspberry Pi board.

''See the [[RaspberryPiBoardDistributions | RPi Distributions]] page for details about the various groups and links to places where you can get involved with building and using RPi Operating Systems.''

''See the [[RPi Programming | RPi Programming]] page for details about the different programming languages and groups which are focusing on them.''

== Other Groups ==

* [https://www.facebook.com/pages/Raspberry-Pi/203296286406503?sk=wall Facebook ]
* [http://www.linkedin.com/groups?about=&gid=4232349 LinkedIn ]
* [https://plus.google.com/107182636490355951240/posts Google Plus]

== Other Pages ==

*[[RPi Education | Educational links]]
*[http://www.raspberrypi.org/forum/general-discussion/conferences-and-other-public-appearances Conferences] (R.Pi Forum thread)
*[http://www.raspberrypprojects.com Raspberry Projects] Multi-User blog site for plans/projects
*[http://www.raspberrypidownload.co.uk RaspberryPi Download] Dedicated Raspberry Pi Mirror
*[https://rpi-developers.com/ RaspberryPi Developers] Independent Forge site for RaspberryPi projects and development.
*[https://www.openindieproject.org Open Indie Project Dot Org] Non-profit organisation developing Open Source projects for use with the RaspberryPi

==References==
<references>
</references>

{{Template:Raspberry Pi}}

RPi Community

2012-05-03T12:13:35Z

Meltwater: /* Raspberry Pi Community e-Magazine */

[[Category:RaspberryPi]]
{{Template:RPi_Learning}}

==About==

The Raspberry Pi Community is steadily growing, so get involved where-ever you want to and share.

'''Please do add links to any Raspberry Pi related forums/subforums/blog pages which focus on the RPi.'''

'''The more the community can connect with one another the better it will be.'''

== Download Mirrors==
Please add a link if you mirror official foundation download images. Please also remove the link when it's no longer available.

[[RPi Download Mirrors]]

== Raspberry Pi Community e-Magazine ==

[http://www.themagpi.com/ The Mag Pi] ([http://themagpi.wordpress.com/ non-flash site])

- Issue 01 May Released -

[http://www.thepiuser.co.uk The Pi User]

Get involved!

Contribute and be part of the [[RPi Community Magazine]] (wiki space for discussion and development of the e-magazine).

==Forums==
*[http://www.raspberrypi.org/forum Official Raspberry Pi Forum] - A great place to share ideas and get the latest information on the Raspberry Pi.

*[http://www.raspberrymod.com/ Raspberrymod.com] - Boost your device, share ideas and knowledge, ask for help and find useful how to's.

*[http://www.raspberrypiforums.com/ RaspberryPiForums.com] - - New Community forum intended to provide Guides and Tutorials for Raspberry Pi Users, and space for users to work on more complex projects.

*[http://www.frambozenbier.org/index.php/raspi-forum Frambozenbier (Raspberry Pi Homebrew)] - These forums are intended to provide practical information about Building, Developing and Sharing information about the Raspberry Pi, in addition to the more "general discussions" that go on in official forums.

*[http://www.edugeek.net/forums/frambozenbier-raspi-forums/ RasPi Forums on EduGeek.net] - Edugeek is a site for Educational network and ICT admins. This is the dedicated Raspberry Pi sections.

*[http://amateurradiopi.org/forum AmateurRadioPi.org Forums] - A forum centered around discussing the interactions between Amateur (HAM) Radio and the Raspberry Pi.

*[http://www.worldofpi.com/ World Of Pi] A forum based on all things Raspberry Pi ranging from basic usage through to programming and electronics/robotics.

==Blogs/News==
* [http://russelldavis.org/ Russell Davis' Blog] - Russell Davis (aka forum admin ukscone) includes posts about the story of the Raspberry Pi, general RPi stuff and other non-Rpi posts too.

* [http://www.pyrosoft.co.uk/blog/ Pyrosoft Paul Maunders' Blog] - Paul Maunders, owner of beta board #8<ref>http://www.pyrosoft.co.uk/blog/2012/01/13/raspberry-pi-8-first-photoshoot/</ref>, provides details about the new board and its use.

* [http://blogs.arcsoftwareconsultancy.com/pi/ Arc Software Consultancy using the Raspberry Pi Blog] - Blogging the experiences of the Arc Software team as they learn about, experiment with and develop software for the Raspberry Pi computer.

* [http://www.raspberrypiblog.com/ Unofficial RPi blog by a software developer]

* [http://raspberrypiblog.ics.com/ ICS Raspberry Pi blog]

* [http://www.cnx-software.com/tag/raspberry-pi/ CNXSoft Blog Raspberry Pi] - Blog posts about the Raspberry Pi including news and how-tos.

* [http://www.raspberryprojects.com/ RaspberryProjects.com] - mutli user blogging for all projects.

* [http://amateurradiopi.org/ AmateurRadioPi.org] - A blog for documenting interactions between amateur radio and the Raspberry Pi.

== Distributions & Development Groups ==
The RPi without an operating system and software to run on it. Many of the groups involved have RPi specific sections and groups working on RPi specific releases and projects.

*[http://wiki.qt-project.org/Qt_RaspberryPi Qt on Raspberry Pi]
The goal of this project is to develop the required enablers for App and Platform Developers to enjoy Qt 5 after investing $35 in a Raspberry Pi board.

''See the [[RaspberryPiBoardDistributions | RPi Distributions]] page for details about the various groups and links to places where you can get involved with building and using RPi Operating Systems.''

''See the [[RPi Programming | RPi Programming]] page for details about the different programming languages and groups which are focusing on them.''

== Other Groups ==

* [https://www.facebook.com/pages/Raspberry-Pi/203296286406503?sk=wall Facebook ]
* [http://www.linkedin.com/groups?about=&gid=4232349 LinkedIn ]
* [https://plus.google.com/107182636490355951240/posts Google Plus]

== Other Pages ==

*[[RPi Education | Educational links]]
*[http://www.raspberrypi.org/forum/general-discussion/conferences-and-other-public-appearances Conferences] (R.Pi Forum thread)
*[http://www.raspberrypprojects.com Raspberry Projects] Multi-User blog site for plans/projects
*[http://www.raspberrypidownload.co.uk RaspberryPi Download] Dedicated Raspberry Pi Mirror
*[https://rpi-developers.com/ RaspberryPi Developers] Independent Forge site for RaspberryPi projects and development.
*[https://www.openindieproject.org Open Indie Project Dot Org] Non-profit organisation developing Open Source projects for use with the RaspberryPi

==References==
<references>
</references>

{{Template:Raspberry Pi}}

RPi Community Magazine

2012-04-30T21:01:10Z

Meltwater: /* Magazine Sites */

[[Category:RaspberryPi]]
{{Template:RPi_Learning}}

=About=
The idea/concept for a Community Magazine has been mentioned several times on the forums, and with a lot of community generated quality content available in various places, it seems like such a magazine can be produced (even if it is an electronic or eMagazine equivalent).

==Forum References==
Here are links to some of the discussions about producing such a magazine (some excellent ideas!):

* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine Slice of Pi/MagPi - Raspberry Pi Magazine]
* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine The Pi User - contributor request!]
* [http://www.raspberrypi.org/forum/off-topic/r-pi-magazine-out-now-cough R-Pi magazine out now (cough)]
* [http://www.raspberrypi.org/forum/general-discussion/raspi-magazine-type-publication-website Raspi magazine (/type publication/website)]
* [http://www.raspberrypi.org/forum/off-topic/raspberry-pi-and-programming-in-linux-for-dummies "RASPBERRY PI (and programming in Linux) FOR DUMMIES"]

A "joke" magazine cover!

[http://www.clivebeale.com/stuff/pimag.pdf Example of Raspberry Pi Magazine Concept] (posted by forum user Clive [http://www.clivebeale.com]).

==Magazine Sites==
There are currently a few sites which are aiming to produce a community magazine.

* [http://www.themagpi.com The Mag Pi] - Issue One Published 30th April 2012
* [http://www.thepiuser.co.uk The Pi User]

==Publication Plans/Ideas==
===Idea/Suggestion: On-line Magazine with periodic eMagazine Publication===
Suggested process:

1. Publish the articles on the blog/site etc as and when they are ready (or perhaps at set point spread over the month/quarter depending on content). Budding writers can even proto-type their articles in the wiki if they feel they need input from others before submitting.

2. The site can be set-up to have a home page with a magazine style index front end, where each regular article gets linked etc. Some basic tile type (metro) index could be quite effective (with hopefully not too much work once setup).

3. Articles can be made available though RSS so people can have the latest article delivered when they are available.

4. After each cycle (whatever the period ends up being), the articles are collected and formulated into a magazine format, ideally nice online flippable format [http://issuu.com/] (suggested by Deep Thought), and of course downloadable format (pdf or ebook etc) which people can read on their ereaders or print out (consideration should be given for b/w printing and reading on ereaders too - separate compact version dropping backgrounds or something?). Again this can probably be delivered through RSS and through kindle (depending on how the magazine subscription process works for kindle).

=Get Involved!=
==Donated Content==
If you are blog writer or you already have content which you are happy to be used in the magazine then please add links here (or create suitable wiki page for the content).

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original - including photos etc).

==Article Ideas==
Add to and list any ideas for articles you would like to see and/or write below.

Note: If you want to write the article within the wiki (so you can get help from others)
then feel free to create a wiki page below for your article, use name "RPi Mag xxxx"
with suitable short name.

==Photographers/illustrators and Images==
A key aspect will be to have some quality images to use in the magazine formatting and presentation.

If you are a keen photographer/illustrator then please send us links to any photos (i.e. on Flicker/Photobucket etc) you have which we can freely use for the magazine. Images can be directly related to using the Raspberry Pi, or abstract (useful for backgrounds and providing style), or perhaps directly related to an article you've seen, or would like to see or want to write.

Perhaps we can include a section as a photography competition too.

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original).

==Editors/Graphic Designers==
In order to produce the formatted version of the magazine we will need some skilful people who can make the content look visually appealing, as well as ensuring the content is correct and legible (typos etc).

==References==
<references>
</references>

{{Template:Raspberry Pi}}

RPi Community Magazine

2012-04-30T21:00:11Z

Meltwater: /* Magazine Sites */

[[Category:RaspberryPi]]
{{Template:RPi_Learning}}

=About=
The idea/concept for a Community Magazine has been mentioned several times on the forums, and with a lot of community generated quality content available in various places, it seems like such a magazine can be produced (even if it is an electronic or eMagazine equivalent).

==Forum References==
Here are links to some of the discussions about producing such a magazine (some excellent ideas!):

* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine Slice of Pi/MagPi - Raspberry Pi Magazine]
* [http://www.raspberrypi.org/forum/educational-applications/slice-of-pi-raspberry-pi-magazine The Pi User - contributor request!]
* [http://www.raspberrypi.org/forum/off-topic/r-pi-magazine-out-now-cough R-Pi magazine out now (cough)]
* [http://www.raspberrypi.org/forum/general-discussion/raspi-magazine-type-publication-website Raspi magazine (/type publication/website)]
* [http://www.raspberrypi.org/forum/off-topic/raspberry-pi-and-programming-in-linux-for-dummies "RASPBERRY PI (and programming in Linux) FOR DUMMIES"]

A "joke" magazine cover!

[http://www.clivebeale.com/stuff/pimag.pdf Example of Raspberry Pi Magazine Concept] (posted by forum user Clive [http://www.clivebeale.com]).

==Magazine Sites==
There are currently a few sites which are aiming to produce a community magazine.

* [http://www.themagpi.com The Mag Pi]
* [http://www.thepiuser.co.uk The Pi User]

==Publication Plans/Ideas==
===Idea/Suggestion: On-line Magazine with periodic eMagazine Publication===
Suggested process:

1. Publish the articles on the blog/site etc as and when they are ready (or perhaps at set point spread over the month/quarter depending on content). Budding writers can even proto-type their articles in the wiki if they feel they need input from others before submitting.

2. The site can be set-up to have a home page with a magazine style index front end, where each regular article gets linked etc. Some basic tile type (metro) index could be quite effective (with hopefully not too much work once setup).

3. Articles can be made available though RSS so people can have the latest article delivered when they are available.

4. After each cycle (whatever the period ends up being), the articles are collected and formulated into a magazine format, ideally nice online flippable format [http://issuu.com/] (suggested by Deep Thought), and of course downloadable format (pdf or ebook etc) which people can read on their ereaders or print out (consideration should be given for b/w printing and reading on ereaders too - separate compact version dropping backgrounds or something?). Again this can probably be delivered through RSS and through kindle (depending on how the magazine subscription process works for kindle).

=Get Involved!=
==Donated Content==
If you are blog writer or you already have content which you are happy to be used in the magazine then please add links here (or create suitable wiki page for the content).

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original - including photos etc).

==Article Ideas==
Add to and list any ideas for articles you would like to see and/or write below.

Note: If you want to write the article within the wiki (so you can get help from others)
then feel free to create a wiki page below for your article, use name "RPi Mag xxxx"
with suitable short name.

==Photographers/illustrators and Images==
A key aspect will be to have some quality images to use in the magazine formatting and presentation.

If you are a keen photographer/illustrator then please send us links to any photos (i.e. on Flicker/Photobucket etc) you have which we can freely use for the magazine. Images can be directly related to using the Raspberry Pi, or abstract (useful for backgrounds and providing style), or perhaps directly related to an article you've seen, or would like to see or want to write.

Perhaps we can include a section as a photography competition too.

Note: Please confirm you are happy for the content to be used (and edited if needed)
in the context of this magazine and to be distributed etc (and your work is
original).

==Editors/Graphic Designers==
In order to produce the formatted version of the magazine we will need some skilful people who can make the content look visually appealing, as well as ensuring the content is correct and legible (typos etc).

==References==
<references>
</references>

{{Template:Raspberry Pi}}

RPi Beginners

2012-04-30T10:17:06Z

Meltwater: /* Media Player */ - added Raspberry Pi goes to the movies

[[Category:RaspberryPi]]
{{Template:RPi_Startup}}

''' INFO : If you are looking for any information related to SD Cards and setup look
[[RPi Easy SD Card Setup | here]] There is some restructuring going on , we are sorry for the inconvenience. '''

=About This Page - For Contributors=
The intention of this page is to provide a '''starting point''' for beginners and to '''direct them to''' the kind of information a person would need in order to start doing something useful or interesting with a Raspberry Pi.

It is not intended to contain or replicate much of the information already available on-line or elsewhere in the wiki, however please create new wiki pages and link them here if there is information beginners will find useful (similarly any section which grows too much here, should be separated into new pages as and when needed)!

At the moment building up ideas of content of typical things beginners will want to know and the kind of things they will want to do first.

----

=Where to start?=
Any easy question to ask, but a very difficult one to answer!
# If you need to get a RPi, the see the [[RPi Buying Guide|Buying Guide]].
# If you need to know what equipment you will need and how to set it up, see the [[RPi Hardware Basic Setup|Basic Hardware Setup]] page.
# If you need to install/setup an SD card see the [[RPi Easy SD Card Setup|Preload your Card]] section.
# If you've done all that, and you are wondering what next...'''welcome and read on!'''

References needed (idea for new section Living Without RPi, which can guide users or link to info to users who haven't got RPis)
Link to emulation builds or live linux cds setup for beginners (RacyPy2 for example)
If you don't have a Raspberry Pi yet, you can still try things out, see xxxx for details.

=What is Linux and why not use Windows?=
Linux is an operating system just like Windows, however, unlike Windows (which needs a set hardware requirement to run i.e. One Size fits or get different hardware), Linux comes in many varieties and configurations which means you can usually find a flavour (or Distribution) which fits your hardware big or small / fast or slow.

The Raspberry Pi is not suited to running Windows due to its hardware, but there are plenty of Linux Distributions which fit nicely. In addition to this, most Distributions of Linux are free, however Windows can cost many times the price of the Raspberry Pi itself.

Chances are you already have Linux running in your home without you even knowing it, since it is commonly used in modern TVs, Freeview and cable boxes to run things and ensure your recording of '''Inbetweeners''' or '''Prison Break''' gets done!

For more information about Linux see
[http://en.wikipedia.org/wiki/Linux Wikipedia]

Also see [http://elinux.org/RPi_End-user_FAQ End-User FAQ]
And [http://elinux.org/Will_RPi_Run Running XXX on the RPi]

=Basic Debian RPi Setup=
When you first turn on your Raspberry Pi with it's fresh Debian image on the SD card, you may have to make some minor adjustments to the OS configuration files to suit your location. The default location setting (locale) is the UK.

==Keyboard Mapping==
If you find that some keys are not working as expected, it is probably the keyboard mapping. To edit the mapping, you have to change it in the /etc/default/keyboard config file. Use sudo to obtain temporary write permissions on the file.
sudo nano /etc/default/keyboard
Change the XKBLAYOUT="gb" to whatever type you need. A common layout is XKBLAYOUT="us". Don't forget to save the file when exiting. Restart to see the changes.

==Change the Timezone==
Unless you live in Great Britain, you'll have to change the default timezone. Use "sudo" to obtain temporary execute permissions.
sudo dpkg-reconfigure tzdata
Follow the prompts to finish the config. The change should be immediate.

=Intro to the CLI (Command Line Interface)=
You will need to use the Command Line Interface at some point in your management of the RPi. The command line interface is a powerful way to interact with the Raspberry Pi and is well worth learning some basic commands to get started with.

For an introductory guide to some basic commands please see: [http://elinux.org/CLI_Spells Command Line Interface "Must Have" Commands]

=Adding more software to your Raspberry pi=
You will probably want to add software to your Raspberry Pi. Here you can find out how to do it.
[http://elinux.org/Add_software Adding Software]

=Beginner Projects=
Here are a few things you can try out with your Raspberry Pi, in most cases all you'll need is your SD Card loaded with a particular preconfigured OS Distribution.

It will be worth getting a few spare SD Cards if you think you will switch between setups regularly or become familiar with how to '''back up and restore''' your card.
Reference needed - a good guide on how to backup and restore cards or software to do this easily

==Media Player==
With this configuration you will typically have the Raspberry Pi connected to a TV or large monitor and a source of videos/music/photos etc you wish to play (i.e. Internet/hard-drive/local network etc).

DesignSpark have done a article on this, which is worth a look, [http://www.designspark.com/content/raspberry-pi-goes-movies DesignSpark - Raspberry Pi goes to the movies]

Reference needed - links to a specific wiki page covering this in detail or links to projects like
OpenElec, CrystalBuntu, Raspbmc etc

==Play Games==
While there are not any commercial games for the Raspberry Pi (yet) there are plenty ways to play games on it.

Many distributions will have games built into them, and some may well support emulation of other platforms so you can run those games.

Also, a lot of Raspberry Pi users will be writing simple games which will be available for others to enjoy (and if desired added to or modified).

Reference needed - game section is empty at the moment!
''See the [[RPi Games|Games Section]] for more details''

==Introducing Young Children To Computers==
Reference needed - some kid friendly and fun stuff!

==Teaching==
There is a huge number of groups, links and resources available within the [[RPi Education|Education]] section.
Reference needed - links to the learning pages, education links and school/university groups

==Learn To Program==
There is a huge selection of [[RPi Programming|programming languages]] which you can use to write interesting programs, games, applications and utilities. There are also more great links within the [[RPi Education#Programming languages|Education]] section.

There is a huge selection to choose from (not just Python...) which should suit any ability and a range of purposes.

If you are new to programming, there are plenty of tutorials for getting started in the [[RPi Tutorials|Tutorials]] Section.

Books about programming can be found in the [[RPi Programming Books|Books]] Section.

In the latest Debian, Python (+Pygame) and MIT Scratch are pre-installed.

Reference needed - links to the learning pages, recommended books?

==Interface With Hardware==
# [[RPi Interfacing with hardware|Interfacing with Arduino]]

Reference needed - links to basic circuits tutorials and expansion boards

==Word Processing/Internet Browsing etc==
Yes, the Raspberry Pi can do the majority of the dull stuff too which other computers do.

'''Debian''' currently comes with Midori installed for web browsing and word processing programs be installed rather easily.

*Entering "sudo apt-get install openoffice.org" into a terminal will install OpenOffice.org, a free Microsoft Office-like application suite
*Entering "sudo apt-get install abiword-common" into a terminal will install AbiWord, a lighter weight but still fully functional word processor

More information needed

==Your Own Pet Project!==
The sky is the limit really, with some time and effort any number of projects can be achieved.

Even if you don't have the skill to do it yourself, you can join like minded people by getting involved with one of the numerous groups in the [[RPi Community|Community Section]], also within the [[RPi Education|Education]] pages or learn what you need in from the [[RPi Guides |Guides]] & [[RPi Tutorials |Tutorials]] sections.

Of course, if you do anything interesting then please let us know in the [[RPi Projects |Projects]] section.

=Living Without RPi=
Even if you do not have any Raspberry Pi hardware there are a number things you can do to learn about linux, programming or even controlling hardware.

==Using Linux==
You can install a version of Linux on most computers, and many you will be able to "try out" Linux by using a "Live CD" - this will start your computer up running from a CD or DVD and run Linux (without installing anything to the computer itself).

RacyPy - This is a simple LiveCD of Puppy Linux which includes some basic programming languages and a light-weight graphical user interface (GUI).

You can get it from here:

[http://teampython.wordpress.com/2012/03/03/while-you-wait-for-your-raspberry-pi-why-not-use-racypy2/ teampython RacyPy]

==Trying Programming==
Many of the programming languages you can use on the Raspberry Pi can be installed on a Windows or Mac machine. Just visit the websites of the languages you are interested in and see if they have an installer for your operating system.

==Controlling Hardware==
As discussed in the [[RPi Tutorial Easy GPIO Hardware & Software | Easy GPIO Hardware & Software]] tutorials, there are lots of alternative hardware you can use to experiment with (some as little as $5).

=References=
<references/>
{{Template:Raspberry Pi}}

RPi Games

2012-04-30T10:02:38Z

Meltwater:

{{Template:RPi_Learning}}

== TOP Games ==
Quake III - See blog article, [http://www.raspberrypi.org/archives/1139 Fancy a Quake III Deathmatch?]

== Types of Game ==

''[[RPi HTML5|HTML5]] - Games to play in a web browser.''

== Game Projects ==
Try making your own games:

[http://www.pygame.org/docs/tut/tom/MakeGames.html Making games with Pygame]

[http://pi-finity.wikia.com/wiki/Pi-finity!_Wiki Pi-finity!] - a 3-D massively multi-player on-line role-playing game system currently under development that will be focused on teaching software development through problem solving in science, math, engineering, technology, economics, social systems, etc. Players will be able to create 3-D worlds, populate them with models for characters, structures, props, scenes, etc., using open-source tools (e.g., Blender) and potentially in-game 3-D modelers. The system will be open-source and very modular, allowing software developers and students to create alternative games and tools based on the fundamental 3-D data structures and inter-player coordination protocols used for the initial games.

RPi Games

2012-04-30T10:00:50Z

Meltwater: /* Game Projects */

{{Template:RPi_Learning}}

== Types of Game ==

''[[RPi HTML5|HTML5]] - Games to play in a web browser.''

== Game Projects ==
Try making your own games:

[http://www.pygame.org/docs/tut/tom/MakeGames.html Making games with Pygame]

[http://pi-finity.wikia.com/wiki/Pi-finity!_Wiki Pi-finity!] - a 3-D massively multi-player on-line role-playing game system currently under development that will be focused on teaching software development through problem solving in science, math, engineering, technology, economics, social systems, etc. Players will be able to create 3-D worlds, populate them with models for characters, structures, props, scenes, etc., using open-source tools (e.g., Blender) and potentially in-game 3-D modelers. The system will be open-source and very modular, allowing software developers and students to create alternative games and tools based on the fundamental 3-D data structures and inter-player coordination protocols used for the initial games.

RPi Beginners

2012-04-30T10:00:11Z

Meltwater: /* Using Linux */

[[Category:RaspberryPi]]
{{Template:RPi_Startup}}

''' INFO : If you are looking for any information related to SD Cards and setup look
[[RPi Easy SD Card Setup | here]] There is some restructuring going on , we are sorry for the inconvenience. '''

=About This Page - For Contributors=
The intention of this page is to provide a '''starting point''' for beginners and to '''direct them to''' the kind of information a person would need in order to start doing something useful or interesting with a Raspberry Pi.

It is not intended to contain or replicate much of the information already available on-line or elsewhere in the wiki, however please create new wiki pages and link them here if there is information beginners will find useful (similarly any section which grows too much here, should be separated into new pages as and when needed)!

At the moment building up ideas of content of typical things beginners will want to know and the kind of things they will want to do first.

----

=Where to start?=
Any easy question to ask, but a very difficult one to answer!
# If you need to get a RPi, the see the [[RPi Buying Guide|Buying Guide]].
# If you need to know what equipment you will need and how to set it up, see the [[RPi Hardware Basic Setup|Basic Hardware Setup]] page.
# If you need to install/setup an SD card see the [[RPi Easy SD Card Setup|Preload your Card]] section.
# If you've done all that, and you are wondering what next...'''welcome and read on!'''

References needed (idea for new section Living Without RPi, which can guide users or link to info to users who haven't got RPis)
Link to emulation builds or live linux cds setup for beginners (RacyPy2 for example)
If you don't have a Raspberry Pi yet, you can still try things out, see xxxx for details.

=What is Linux and why not use Windows?=
Linux is an operating system just like Windows, however, unlike Windows (which needs a set hardware requirement to run i.e. One Size fits or get different hardware), Linux comes in many varieties and configurations which means you can usually find a flavour (or Distribution) which fits your hardware big or small / fast or slow.

The Raspberry Pi is not suited to running Windows due to its hardware, but there are plenty of Linux Distributions which fit nicely. In addition to this, most Distributions of Linux are free, however Windows can cost many times the price of the Raspberry Pi itself.

Chances are you already have Linux running in your home without you even knowing it, since it is commonly used in modern TVs, Freeview and cable boxes to run things and ensure your recording of '''Inbetweeners''' or '''Prison Break''' gets done!

For more information about Linux see
[http://en.wikipedia.org/wiki/Linux Wikipedia]

Also see [http://elinux.org/RPi_End-user_FAQ End-User FAQ]
And [http://elinux.org/Will_RPi_Run Running XXX on the RPi]

=Basic Debian RPi Setup=
When you first turn on your Raspberry Pi with it's fresh Debian image on the SD card, you may have to make some minor adjustments to the OS configuration files to suit your location. The default location setting (locale) is the UK.

==Keyboard Mapping==
If you find that some keys are not working as expected, it is probably the keyboard mapping. To edit the mapping, you have to change it in the /etc/default/keyboard config file. Use sudo to obtain temporary write permissions on the file.
sudo nano /etc/default/keyboard
Change the XKBLAYOUT="gb" to whatever type you need. A common layout is XKBLAYOUT="us". Don't forget to save the file when exiting. Restart to see the changes.

==Change the Timezone==
Unless you live in Great Britain, you'll have to change the default timezone. Use "sudo" to obtain temporary execute permissions.
sudo dpkg-reconfigure tzdata
Follow the prompts to finish the config. The change should be immediate.

=Intro to the CLI (Command Line Interface)=
You will need to use the Command Line Interface at some point in your management of the RPi. The command line interface is a powerful way to interact with the Raspberry Pi and is well worth learning some basic commands to get started with.

For an introductory guide to some basic commands please see: [http://elinux.org/CLI_Spells Command Line Interface "Must Have" Commands]

=Adding more software to your Raspberry pi=
You will probably want to add software to your Raspberry Pi. Here you can find out how to do it.
[http://elinux.org/Add_software Adding Software]

=Beginner Projects=
Here are a few things you can try out with your Raspberry Pi, in most cases all you'll need is your SD Card loaded with a particular preconfigured OS Distribution.

It will be worth getting a few spare SD Cards if you think you will switch between setups regularly or become familiar with how to '''back up and restore''' your card.
Reference needed - a good guide on how to backup and restore cards or software to do this easily

==Media Player==
With this configuration you will typically have the Raspberry Pi connected to a TV or large monitor and a source of videos/music/photos etc you wish to play (i.e. Internet/hard-drive/local network etc).

Reference needed - links to a specific wiki page covering this in detail or links to projects like
OpenElec, CrystalBuntu, Raspbmc etc

==Play Games==
While there are not any commercial games for the Raspberry Pi (yet) there are plenty ways to play games on it.

Many distributions will have games built into them, and some may well support emulation of other platforms so you can run those games.

Also, a lot of Raspberry Pi users will be writing simple games which will be available for others to enjoy (and if desired added to or modified).

Reference needed - game section is empty at the moment!
''See the [[RPi Games|Games Section]] for more details''

==Introducing Young Children To Computers==
Reference needed - some kid friendly and fun stuff!

==Teaching==
There is a huge number of groups, links and resources available within the [[RPi Education|Education]] section.
Reference needed - links to the learning pages, education links and school/university groups

==Learn To Program==
There is a huge selection of [[RPi Programming|programming languages]] which you can use to write interesting programs, games, applications and utilities. There are also more great links within the [[RPi Education#Programming languages|Education]] section.

There is a huge selection to choose from (not just Python...) which should suit any ability and a range of purposes.

If you are new to programming, there are plenty of tutorials for getting started in the [[RPi Tutorials|Tutorials]] Section.

Books about programming can be found in the [[RPi Programming Books|Books]] Section.

In the latest Debian, Python (+Pygame) and MIT Scratch are pre-installed.

Reference needed - links to the learning pages, recommended books?

==Interface With Hardware==
# [[RPi Interfacing with hardware|Interfacing with Arduino]]

Reference needed - links to basic circuits tutorials and expansion boards

==Word Processing/Internet Browsing etc==
Yes, the Raspberry Pi can do the majority of the dull stuff too which other computers do.

'''Debian''' currently comes with Midori installed for web browsing and word processing programs be installed rather easily.

*Entering "sudo apt-get install openoffice.org" into a terminal will install OpenOffice.org, a free Microsoft Office-like application suite
*Entering "sudo apt-get install abiword-common" into a terminal will install AbiWord, a lighter weight but still fully functional word processor

More information needed

==Your Own Pet Project!==
The sky is the limit really, with some time and effort any number of projects can be achieved.

Even if you don't have the skill to do it yourself, you can join like minded people by getting involved with one of the numerous groups in the [[RPi Community|Community Section]], also within the [[RPi Education|Education]] pages or learn what you need in from the [[RPi Guides |Guides]] & [[RPi Tutorials |Tutorials]] sections.

Of course, if you do anything interesting then please let us know in the [[RPi Projects |Projects]] section.

=Living Without RPi=
Even if you do not have any Raspberry Pi hardware there are a number things you can do to learn about linux, programming or even controlling hardware.

==Using Linux==
You can install a version of Linux on most computers, and many you will be able to "try out" Linux by using a "Live CD" - this will start your computer up running from a CD or DVD and run Linux (without installing anything to the computer itself).

RacyPy - This is a simple LiveCD of Puppy Linux which includes some basic programming languages and a light-weight graphical user interface (GUI).

You can get it from here:

[http://teampython.wordpress.com/2012/03/03/while-you-wait-for-your-raspberry-pi-why-not-use-racypy2/ teampython RacyPy]

==Trying Programming==
Many of the programming languages you can use on the Raspberry Pi can be installed on a Windows or Mac machine. Just visit the websites of the languages you are interested in and see if they have an installer for your operating system.

==Controlling Hardware==
As discussed in the [[RPi Tutorial Easy GPIO Hardware & Software | Easy GPIO Hardware & Software]] tutorials, there are lots of alternative hardware you can use to experiment with (some as little as $5).

=References=
<references/>
{{Template:Raspberry Pi}}

RPi Beginners

2012-04-30T09:53:25Z

Meltwater: /* What is Linux and why not use Windows? */

[[Category:RaspberryPi]]
{{Template:RPi_Startup}}

''' INFO : If you are looking for any information related to SD Cards and setup look
[[RPi Easy SD Card Setup | here]] There is some restructuring going on , we are sorry for the inconvenience. '''

=About This Page - For Contributors=
The intention of this page is to provide a '''starting point''' for beginners and to '''direct them to''' the kind of information a person would need in order to start doing something useful or interesting with a Raspberry Pi.

It is not intended to contain or replicate much of the information already available on-line or elsewhere in the wiki, however please create new wiki pages and link them here if there is information beginners will find useful (similarly any section which grows too much here, should be separated into new pages as and when needed)!

At the moment building up ideas of content of typical things beginners will want to know and the kind of things they will want to do first.

----

=Where to start?=
Any easy question to ask, but a very difficult one to answer!
# If you need to get a RPi, the see the [[RPi Buying Guide|Buying Guide]].
# If you need to know what equipment you will need and how to set it up, see the [[RPi Hardware Basic Setup|Basic Hardware Setup]] page.
# If you need to install/setup an SD card see the [[RPi Easy SD Card Setup|Preload your Card]] section.
# If you've done all that, and you are wondering what next...'''welcome and read on!'''

References needed (idea for new section Living Without RPi, which can guide users or link to info to users who haven't got RPis)
Link to emulation builds or live linux cds setup for beginners (RacyPy2 for example)
If you don't have a Raspberry Pi yet, you can still try things out, see xxxx for details.

=What is Linux and why not use Windows?=
Linux is an operating system just like Windows, however, unlike Windows (which needs a set hardware requirement to run i.e. One Size fits or get different hardware), Linux comes in many varieties and configurations which means you can usually find a flavour (or Distribution) which fits your hardware big or small / fast or slow.

The Raspberry Pi is not suited to running Windows due to its hardware, but there are plenty of Linux Distributions which fit nicely. In addition to this, most Distributions of Linux are free, however Windows can cost many times the price of the Raspberry Pi itself.

Chances are you already have Linux running in your home without you even knowing it, since it is commonly used in modern TVs, Freeview and cable boxes to run things and ensure your recording of '''Inbetweeners''' or '''Prison Break''' gets done!

For more information about Linux see
[http://en.wikipedia.org/wiki/Linux Wikipedia]

Also see [http://elinux.org/RPi_End-user_FAQ End-User FAQ]
And [http://elinux.org/Will_RPi_Run Running XXX on the RPi]

=Basic Debian RPi Setup=
When you first turn on your Raspberry Pi with it's fresh Debian image on the SD card, you may have to make some minor adjustments to the OS configuration files to suit your location. The default location setting (locale) is the UK.

==Keyboard Mapping==
If you find that some keys are not working as expected, it is probably the keyboard mapping. To edit the mapping, you have to change it in the /etc/default/keyboard config file. Use sudo to obtain temporary write permissions on the file.
sudo nano /etc/default/keyboard
Change the XKBLAYOUT="gb" to whatever type you need. A common layout is XKBLAYOUT="us". Don't forget to save the file when exiting. Restart to see the changes.

==Change the Timezone==
Unless you live in Great Britain, you'll have to change the default timezone. Use "sudo" to obtain temporary execute permissions.
sudo dpkg-reconfigure tzdata
Follow the prompts to finish the config. The change should be immediate.

=Intro to the CLI (Command Line Interface)=
You will need to use the Command Line Interface at some point in your management of the RPi. The command line interface is a powerful way to interact with the Raspberry Pi and is well worth learning some basic commands to get started with.

For an introductory guide to some basic commands please see: [http://elinux.org/CLI_Spells Command Line Interface "Must Have" Commands]

=Adding more software to your Raspberry pi=
You will probably want to add software to your Raspberry Pi. Here you can find out how to do it.
[http://elinux.org/Add_software Adding Software]

=Beginner Projects=
Here are a few things you can try out with your Raspberry Pi, in most cases all you'll need is your SD Card loaded with a particular preconfigured OS Distribution.

It will be worth getting a few spare SD Cards if you think you will switch between setups regularly or become familiar with how to '''back up and restore''' your card.
Reference needed - a good guide on how to backup and restore cards or software to do this easily

==Media Player==
With this configuration you will typically have the Raspberry Pi connected to a TV or large monitor and a source of videos/music/photos etc you wish to play (i.e. Internet/hard-drive/local network etc).

Reference needed - links to a specific wiki page covering this in detail or links to projects like
OpenElec, CrystalBuntu, Raspbmc etc

==Play Games==
While there are not any commercial games for the Raspberry Pi (yet) there are plenty ways to play games on it.

Many distributions will have games built into them, and some may well support emulation of other platforms so you can run those games.

Also, a lot of Raspberry Pi users will be writing simple games which will be available for others to enjoy (and if desired added to or modified).

Reference needed - game section is empty at the moment!
''See the [[RPi Games|Games Section]] for more details''

==Introducing Young Children To Computers==
Reference needed - some kid friendly and fun stuff!

==Teaching==
There is a huge number of groups, links and resources available within the [[RPi Education|Education]] section.
Reference needed - links to the learning pages, education links and school/university groups

==Learn To Program==
There is a huge selection of [[RPi Programming|programming languages]] which you can use to write interesting programs, games, applications and utilities. There are also more great links within the [[RPi Education#Programming languages|Education]] section.

There is a huge selection to choose from (not just Python...) which should suit any ability and a range of purposes.

If you are new to programming, there are plenty of tutorials for getting started in the [[RPi Tutorials|Tutorials]] Section.

Books about programming can be found in the [[RPi Programming Books|Books]] Section.

In the latest Debian, Python (+Pygame) and MIT Scratch are pre-installed.

Reference needed - links to the learning pages, recommended books?

==Interface With Hardware==
# [[RPi Interfacing with hardware|Interfacing with Arduino]]

Reference needed - links to basic circuits tutorials and expansion boards

==Word Processing/Internet Browsing etc==
Yes, the Raspberry Pi can do the majority of the dull stuff too which other computers do.

'''Debian''' currently comes with Midori installed for web browsing and word processing programs be installed rather easily.

*Entering "sudo apt-get install openoffice.org" into a terminal will install OpenOffice.org, a free Microsoft Office-like application suite
*Entering "sudo apt-get install abiword-common" into a terminal will install AbiWord, a lighter weight but still fully functional word processor

More information needed

==Your Own Pet Project!==
The sky is the limit really, with some time and effort any number of projects can be achieved.

Even if you don't have the skill to do it yourself, you can join like minded people by getting involved with one of the numerous groups in the [[RPi Community|Community Section]], also within the [[RPi Education|Education]] pages or learn what you need in from the [[RPi Guides |Guides]] & [[RPi Tutorials |Tutorials]] sections.

Of course, if you do anything interesting then please let us know in the [[RPi Projects |Projects]] section.

=Living Without RPi=
Even if you do not have any Raspberry Pi hardware there are a number things you can do to learn about linux, programming or even controlling hardware.

==Using Linux==
You can install a version of Linux on most computers, and many you will be able to "try out" Linux by using a "Live CD" - this will start your computer up running from a CD or DVD and run Linux (without installing anything to the computer itself).

==Trying Programming==
Many of the programming languages you can use on the Raspberry Pi can be installed on a Windows or Mac machine. Just visit the websites of the languages you are interested in and see if they have an installer for your operating system.

==Controlling Hardware==
As discussed in the [[RPi Tutorial Easy GPIO Hardware & Software | Easy GPIO Hardware & Software]] tutorials, there are lots of alternative hardware you can use to experiment with (some as little as $5).

=References=
<references/>
{{Template:Raspberry Pi}}

RPi Beginners

2012-04-30T09:52:30Z

Meltwater: /* References */

[[Category:RaspberryPi]]
{{Template:RPi_Startup}}

''' INFO : If you are looking for any information related to SD Cards and setup look
[[RPi Easy SD Card Setup | here]] There is some restructuring going on , we are sorry for the inconvenience. '''

=About This Page - For Contributors=
The intention of this page is to provide a '''starting point''' for beginners and to '''direct them to''' the kind of information a person would need in order to start doing something useful or interesting with a Raspberry Pi.

It is not intended to contain or replicate much of the information already available on-line or elsewhere in the wiki, however please create new wiki pages and link them here if there is information beginners will find useful (similarly any section which grows too much here, should be separated into new pages as and when needed)!

At the moment building up ideas of content of typical things beginners will want to know and the kind of things they will want to do first.

----

=Where to start?=
Any easy question to ask, but a very difficult one to answer!
# If you need to get a RPi, the see the [[RPi Buying Guide|Buying Guide]].
# If you need to know what equipment you will need and how to set it up, see the [[RPi Hardware Basic Setup|Basic Hardware Setup]] page.
# If you need to install/setup an SD card see the [[RPi Easy SD Card Setup|Preload your Card]] section.
# If you've done all that, and you are wondering what next...'''welcome and read on!'''

References needed (idea for new section Living Without RPi, which can guide users or link to info to users who haven't got RPis)
Link to emulation builds or live linux cds setup for beginners (RacyPy2 for example)
If you don't have a Raspberry Pi yet, you can still try things out, see xxxx for details.

=What is Linux and why not use Windows?=
Linux is an operating system just like Windows, however, unlike Windows (which needs a set hardware requirement to run i.e. One Size fits or get different hardware), Linux comes in many varieties and configurations which means you can usually find a flavour (or Distribution) which fits your hardware big or small / fast or slow.

The Raspberry Pi is not suited to running Windows due to its hardware, but there are plenty of Linux Distributions which fit nicely. In addition to this, most Distributions of Linux are free, however Windows can cost many times the price of the Raspberry Pi itself.

Chances are you already have Linux running in your home without you even knowing it, since it is commonly used in modern TVs, Freeview and cable boxes to run things and ensure your recording of '''Inbetweeners''' gets done!

For more information about Linux see
[http://en.wikipedia.org/wiki/Linux Wikipedia]

Also see [http://elinux.org/RPi_End-user_FAQ End-User FAQ]
And [http://elinux.org/Will_RPi_Run Running XXX on the RPi]

=Basic Debian RPi Setup=
When you first turn on your Raspberry Pi with it's fresh Debian image on the SD card, you may have to make some minor adjustments to the OS configuration files to suit your location. The default location setting (locale) is the UK.

==Keyboard Mapping==
If you find that some keys are not working as expected, it is probably the keyboard mapping. To edit the mapping, you have to change it in the /etc/default/keyboard config file. Use sudo to obtain temporary write permissions on the file.
sudo nano /etc/default/keyboard
Change the XKBLAYOUT="gb" to whatever type you need. A common layout is XKBLAYOUT="us". Don't forget to save the file when exiting. Restart to see the changes.

==Change the Timezone==
Unless you live in Great Britain, you'll have to change the default timezone. Use "sudo" to obtain temporary execute permissions.
sudo dpkg-reconfigure tzdata
Follow the prompts to finish the config. The change should be immediate.

=Intro to the CLI (Command Line Interface)=
You will need to use the Command Line Interface at some point in your management of the RPi. The command line interface is a powerful way to interact with the Raspberry Pi and is well worth learning some basic commands to get started with.

For an introductory guide to some basic commands please see: [http://elinux.org/CLI_Spells Command Line Interface "Must Have" Commands]

=Adding more software to your Raspberry pi=
You will probably want to add software to your Raspberry Pi. Here you can find out how to do it.
[http://elinux.org/Add_software Adding Software]

=Beginner Projects=
Here are a few things you can try out with your Raspberry Pi, in most cases all you'll need is your SD Card loaded with a particular preconfigured OS Distribution.

It will be worth getting a few spare SD Cards if you think you will switch between setups regularly or become familiar with how to '''back up and restore''' your card.
Reference needed - a good guide on how to backup and restore cards or software to do this easily

==Media Player==
With this configuration you will typically have the Raspberry Pi connected to a TV or large monitor and a source of videos/music/photos etc you wish to play (i.e. Internet/hard-drive/local network etc).

Reference needed - links to a specific wiki page covering this in detail or links to projects like
OpenElec, CrystalBuntu, Raspbmc etc

==Play Games==
While there are not any commercial games for the Raspberry Pi (yet) there are plenty ways to play games on it.

Many distributions will have games built into them, and some may well support emulation of other platforms so you can run those games.

Also, a lot of Raspberry Pi users will be writing simple games which will be available for others to enjoy (and if desired added to or modified).

Reference needed - game section is empty at the moment!
''See the [[RPi Games|Games Section]] for more details''

==Introducing Young Children To Computers==
Reference needed - some kid friendly and fun stuff!

==Teaching==
There is a huge number of groups, links and resources available within the [[RPi Education|Education]] section.
Reference needed - links to the learning pages, education links and school/university groups

==Learn To Program==
There is a huge selection of [[RPi Programming|programming languages]] which you can use to write interesting programs, games, applications and utilities. There are also more great links within the [[RPi Education#Programming languages|Education]] section.

There is a huge selection to choose from (not just Python...) which should suit any ability and a range of purposes.

If you are new to programming, there are plenty of tutorials for getting started in the [[RPi Tutorials|Tutorials]] Section.

Books about programming can be found in the [[RPi Programming Books|Books]] Section.

In the latest Debian, Python (+Pygame) and MIT Scratch are pre-installed.

Reference needed - links to the learning pages, recommended books?

==Interface With Hardware==
# [[RPi Interfacing with hardware|Interfacing with Arduino]]

Reference needed - links to basic circuits tutorials and expansion boards

==Word Processing/Internet Browsing etc==
Yes, the Raspberry Pi can do the majority of the dull stuff too which other computers do.

'''Debian''' currently comes with Midori installed for web browsing and word processing programs be installed rather easily.

*Entering "sudo apt-get install openoffice.org" into a terminal will install OpenOffice.org, a free Microsoft Office-like application suite
*Entering "sudo apt-get install abiword-common" into a terminal will install AbiWord, a lighter weight but still fully functional word processor

More information needed

==Your Own Pet Project!==
The sky is the limit really, with some time and effort any number of projects can be achieved.

Even if you don't have the skill to do it yourself, you can join like minded people by getting involved with one of the numerous groups in the [[RPi Community|Community Section]], also within the [[RPi Education|Education]] pages or learn what you need in from the [[RPi Guides |Guides]] & [[RPi Tutorials |Tutorials]] sections.

Of course, if you do anything interesting then please let us know in the [[RPi Projects |Projects]] section.

=Living Without RPi=
Even if you do not have any Raspberry Pi hardware there are a number things you can do to learn about linux, programming or even controlling hardware.

==Using Linux==
You can install a version of Linux on most computers, and many you will be able to "try out" Linux by using a "Live CD" - this will start your computer up running from a CD or DVD and run Linux (without installing anything to the computer itself).

==Trying Programming==
Many of the programming languages you can use on the Raspberry Pi can be installed on a Windows or Mac machine. Just visit the websites of the languages you are interested in and see if they have an installer for your operating system.

==Controlling Hardware==
As discussed in the [[RPi Tutorial Easy GPIO Hardware & Software | Easy GPIO Hardware & Software]] tutorials, there are lots of alternative hardware you can use to experiment with (some as little as $5).

=References=
<references/>
{{Template:Raspberry Pi}}

RPi Hub

2012-04-30T09:40:22Z

Meltwater: /* Beginners Guide */

{{TOC right}}{{Template:Hub_Flags}} 
{{Clear}}
'''The Raspberry Pi wiki pages on this site are a community work - the Raspberry Pi Foundation is not responsible for content on these pages.'''

==Now shipping to customers==
Premier Farnell and RS Components have started shipping to customers. Congratulations to those at the front of the queue!.

Work is ongoing to clear the backlog of orders, with both distributors now manufacturing them in serial production. Farnell/Element14 have stated that all people worldwide who ordered their Raspberry Pi through them on or before April 18th should receive theirs by the end of June.

See the [[RPi Buying Guide | Buying Guide]] on how to order one, or visit the [http://www.raspberrypi.org Raspberry Pi Foundation Home Page]

==About==
[[File:RpiFront.jpg|300px|thumb|right|The Rpi beta board (model B)]]

The Raspberry Pi (short: RPi or RasPi) is an ultra-low-cost credit-card sized Linux computer which was conceived with the primary goal of teaching computer programming to children. It was developed by the [http://www.raspberrypi.org Raspberry Pi Foundation], which is a UK registered charity (Registration Number 1129409). The foundation exists to promote the study of computer science and related topics, especially at school level, and to put the fun back into learning computing. We expect this computer to have many other applications both in the developed and the developing world ([[RPi_Philosophy|Read more]]).

* You can get the latest news from the [http://www.raspberrypi.org Foundation Home Page], the [http://twitter.com/intent/user?screen_name=Raspberry_Pi Twitter Feed] or in the [http://www.raspberrypi.org/forum/general-discussion/news-articles-and-blog-posts-about-raspberry-pi forums].
* For Raspberry Pi frequently asked questions see the [[R-Pi FAQ]] or the [http://www.raspberrypi.org/?page_id=8 Raspberry Pi Foundation's FAQ] page.
* Products are RoHS, CE, FCC, CTick and CSA compliant. Please contact the distributor from whom you purchased your Raspberry Pi device for details regarding WEEE in your country.
* Expected cost: ~16GBP or 25USD Model A, ~23GBP or 35USD for Model B. For information about availability and shipping see the [[RPi Buying Guide | Buying Guide]].

===History===
* Confused about seeing different versions of the board? Visit the [[Rpi HardwareHistory | History of the Raspberry Pi Hardware]] for information about the past versions.

* RegHardware's very detailed analysis is [http://www.reghardware.com/2011/11/28/raspberry_pi/ well worth a read]. Wikipedia also has [http://en.wikipedia.org/wiki/Raspberry_Pi an entry].

* Russell Davis (aka forum admin [[ukscone]]) has a series of blog articles recording his perspective of the [http://russelldavis.org/2012/01/14/the-raspberry-pi-part-one/ Raspberry Pi story] in several parts from the beginning.

* You will often hear mention of the BBC Micro Computer when people talk about the purpose of the Raspberry Pi Foundation. See this article on the [http://www.reghardware.com/2011/11/30/bbc_micro_model_b_30th_anniversary/ history of the BBC Micro Computer].

* Here's a video from the Financial Times, with three different groups evaluating the raspberry pi: http://video.ft.com/v/1498254373001/Taste-testing-the-Raspberry-Pi (March 2012)

==Getting Started==
{| border="1" style="background:transparent;"
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===[[Buying RPi |Buying Guide]]===
----
Where can I get one and for how much?
* Raspberry Pi can only be purchased via their official distribution partners - detailed information can be found on the [[Buying RPi | RPi Buying Guide]] page.

* Additional accessories, peripherals and merchandise will also be available through the [http://www.raspberrypi.com/ Raspberry Pi Shop].

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===[[RPi Hardware Basic Setup | Basic Setup]]===
----
First little Raspberry Pi Steps...
* Ensure you have all the [[RPi Hardware Basic Setup#Typical_Hardware_You_Will_Need |equipment]] you need to go with your Raspberry Pi.
* Become familiar with the [[RPi Hardware Basic Setup#Connecting_Together | board layout and connect]] it ready for power up.
* If you have not been provided with a pre-setup SD card you will need to prepare one with your chosen [[RPi_Easy_SD_Card_Setup | Operating System distribution]]

* '''Having problems? Try the [http://elinux.org/R-Pi_Troubleshooting Troubleshooting] page.'''

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===[[RPi Beginners | Beginners Guide]]===
----
You've just got your new Raspberry Pi device - what now?
* [[RPi Beginners | Beginners Guide]]

* Learn about the basics with the [http://h2g2.com/dna/h2g2/A13735596 H2G2 - Introducing the Raspberry Pi] entry.

* Get started with some basic projects and tutorials:
[http://www.youtube.com/user/RaspberryPiTutorials Raspberry Pi YouTube Tutorials]

[[RPi Tutorial Easy GPIO Hardware & Software | Easy GPIO Hardware & Software]] - in-progress at the moment
Example projects/tuts which can be linked from here
(or from within a beginners guide page perhaps):
Setup XBMC media centre
Programming tutorials (Liams YouTube etc)
Easy GPIO (when complete or similar thing).
Also links to some basic linux user guides.

* Take a look through the [[R-Pi_Hub#Community|Community]] section, which contains a range of beginner and advanced tutorials and guides, as well as groups to help you find like-minded developers.

|}

==Resources==
{| border="1" style="background:transparent;"

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===[[RPi Hardware|Hardware]] & [[RPi VerifiedPeripherals|Peripherals]]===
----

*The Model B is more advanced than the Model A - see [[RPi Hardware]].
*The RPi can be plugged into a [[RPi Screens|suitable TV or monitor]].
*The unit will support a range of [[RPi VerifiedPeripherals |USB devices, peripherals and accessories]].
*The [[Rpi Low-level peripherals| Low-level interfaces]] allow the use of optional [[RPi Expansion Boards|Expansion Boards]] in a wide range of projects.
*For more advanced issues including see [[RPi Advanced Setup|Advanced Setup]].
*[[RPi Peripherals|Setting up peripherals - examples/HowTos]]
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===[[Rpi_Software|Software]] & [[RPi_Distributions|OS Distributions]]===
----
The Raspberry Pi will run a range of OS Distributions and run a variety of software.
* See [[RPi Software|Software]] for an overview, and [[RPi Distributions|OS Distributions]] for supported operating system and pre-configured 'images'.
*Main OS distributions include [[RPi Distributions#Debian_ARM | Debian ARM]], [[RPi Distributions#Fedora | Fedora]], [[RPi Distributions#KidsRuby | KidsRuby]] and [http://puppylinux.org/wikka/Puppi Puppi] from Puppy Linux.
*Advice is also available if you want to [[Rpi_kernel_compilation|compile a kernel]] or [[RPi_Performance|test the Pi's performance]].
*The Raspberry Pi supports a wide range of [[RPi Programming|programming languages]], with many tutorials available.
*Information about installing specific [[RPi_applications|applications]] is available through the link.

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===[[RPi Documentation|Documentation]]===
----
Documentation relating to the Raspberry Pi can be found [[RPi Documentation|here]].

[[RPi DatasheetCategories|Frambozenier.org Documentation Project Datasheets]]

Example documents which can be linked from here (or sub page):
Official Datasheets
White Papers
User Manuals
Recommended books (perhaps)

===[[R-Pi Troubleshooting|How to fix common problems]]===
|}

==Community==
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===[[RPi Projects |Projects]], [[RPi Guides |Guides]] & [[RPi Tutorials |Tutorials]]===
----
*An important source of information and guides is the [http://www.raspberrypi.org/forum Official Forum].
*Knowledgeable users may want to review and help out with the [[RPi Tasks |Tasks page]].
*Get started by following some of the many [[RPi Tutorials | Tutorials]].
*Common tasks and useful tip are available through the [[RPi Guides | Guides page]].
*Projects can be found, and added to, on the [[RPi Projects |Projects page]].

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===[[Rpi Education|Schools, Universities, Clubs & Groups]]===
----
*The Raspberry Pi Foundation's aims include encouraging education. Several groups including [http://www.computingatschool.org.uk/ Computing At School] aim to bring Computing Science back into schools.
*Go to the [[Rpi Education|Education Page]] to add your project and find helpful links.

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===[[RPi Community |Supporting Communities]]===
----
The [[RPi Community |Raspberry Pi Community]] is steadily growing:
*[http://www.raspberrypi.org/forum The Official Raspberry Pi Forum]

*[http://www.frambozenbier.org/index.php/ 'Frambozenbier' (Raspberry Pi Homebrew)]

*[http://www.raspberrymod.com/ Raspberrymod] and [http://www.raspberrypiforums.com/forum RPiforums] Un-Official Raspberry Pi Discussion Boards

*[http://www.raspberrypi-spanish.es Non-official community of Raspberry Pi in spanish language]

*[http://www.worldofpi/com/ World Of Pi] A forum based on all things Raspberry Pi.

*[[RPi Community Magazine]] - User contributed eMagazine, get involved!
|}

==About the RPi Wiki==

'''Do not be afraid to add your bit, content is vital for the wiki to function.'''

[[File:Rasp_turn_around.gif|200px|thumb|right|A 3D rendering of the Raspberry Pi logo by forum user Antario. [http://www.raspberrypi.org/forum/projects-and-collaboration-general/raspberry-pi-3d-logo-animation Source]]]
This wiki is '''open''' for the community. You are encouraged to sign up and add your own projects, guides and correct anything within it. It is important that users like you continue to add to and grow this wiki, that way others will be able to come and do the same making the wiki a valuable resource. See [[Help:Editing | Help Editing The Wiki]] and the [[Special:Upload | Upload File]] link (on the left sidebar) to reference images.
Have a look at our [[RPi Wiki Best Practice|Guidelines]] and then you are free to go !

=== Translations ===

The wiki is being translated into several languages, some of which can be seen on the hub banner above. Current languages include:

* English: [[R-Pi Hub]]
* French: [[FR:R-Pi Hub]]
* German: [[DE:R-Pi Hub]]
* Greek: [[EL:R-Pi Hub]]
* Hungarian: [[HU:R-Pi Hub]]
* Japanese: [[JP:R-Pi_Hub]]
* Polish: [[PL:R-Pi_Hub]]
* Portugese: [[pt-BR:Raspberry Pi Board]]
* Romanian: [[RO:R-Pi_Hub]]
* Russian: [[RU:RaspberryPiBoard]]
* Spanish: [[ES:R-Pi Hub]]
* Italiano: [[IT:R-Pi Hub]]
* Chinese:[[CH:R-Pi Hub]]

Any help translating would be greatly appreciated. Thank you to those who have already contributed!

===Admins/Contributors===

Please see the [[Talk:R-Pi_Hub|Talk]] page for outstanding issues and discussions regarding the RPi Hub and related pages. 
Also , have look at [[RPi Wiki Best Practice]]. You can discuss the recommendations
[[Talk:RPi Wiki Best Practice | here ]] .

To share your thoughts, comments, thanks and interesting articles, see our [[RPi Visitor Book |Visitor Book]].

''Big thanks to elinux.org and their groups for the wiki space and content from which these pages have been grown.''

=References=
<references/>

{{Template:Raspberry Pi}}
[[Category:RaspberryPi]]

RPi Documentation

2012-04-26T10:32:35Z

Meltwater: /* Schematics */

{{Template:RPi Resources}}

Note: All datasheets, documents and Trademarks remain the property of their respective owners.

=Published Datasheets=
==User Guides==
[http://elinux.org/File:Raspi-Model-AB-Mono-2-699x1024.png Raspberry Pi Model A/Model B Layout Diagram]
==Hardware / Software Datasheets==
===Raspberry Pi Processor Broadcom System-On-Chip:===
[http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf BCM2835 ARM Peripherals] - ([[BCM2835 datasheet errata]])

[http://www.scribd.com/doc/91353537/GPIO-Pads-Control GPIO Datasheet Addendum - GPIO Pads Control]

===ARM 11 CPU Core:===
[http://infocenter.arm.com/help/topic/com.arm.doc.ddi0301h/DDI0301H_arm1176jzfs_r0p7_trm.pdf (ARM1176JZF-S)]

===Model B LAN Chip:===
[http://www.smsc.com/media/Downloads_Public/Data_Briefs/9512db.pdf (LAN9512) Data Brief] | [http://www.smsc.com/media/Downloads_Public/Data_Sheets/9512.pdf (LAN9512) Datasheet])

==Mechanical Data==
===Production Boards (2012 Q1):===
none available yet
===Beta Boards:===
[http://www.scribd.com/doc/77785093/Raspberry-Pi-initial-Beta-boards-Mechanical Gert's Beta Boards Mechanical Data]

==Schematics==
===Production Boards (2012 Q1):===
[http://www.raspberrypi.org/wp-content/uploads/2012/04/Raspberry-Pi-Schematics-R1.0.pdf Raspberry Pi Electrical Schematics]
===Beta Boards:===
[http://www.raspberrypi.org/wp-content/uploads/2011/11/gerbers2.png Beta Board PCB Layers Screenshot]

[http://lh3.googleusercontent.com/-uO4l8pwSLvU/TsQGbth6x6I/AAAAAAAAAkk/5zQMH3uKPiE/s829/Boardlayout.png Beta Board PCB Layers Screenshot, labelled version]

=Additional Published Information=
==Gert Board:==
[http://www.scribd.com/doc/88286916/Gertboard-Overview Gertboard-Overview]

==Power Supply Details:==
[http://www.scribd.com/doc/69700160/Rasp-Why-Does-It-Use-More-Power Detailed explanation of the Beta board power supply]

[http://www.raspberrypi.org/wp-content/uploads/2011/12/psu.png Preliminary power supply schematic, Beta board]

=Documentation Projects=
==Frambozenier.org Datasheets:==
[[RPi DatasheetCategories | Frambozenier.org Documentation Project Datasheets]] - Selection of detailed datasheets on the Raspberry Pi (developed on the wiki, reviewed then published).

{{Template:Raspberry Pi}}

RPi Low-level peripherals

2012-04-26T10:29:18Z

Meltwater: /* General Purpose Input/Output (GPIO) */ - added note about GPIO-Pads-Control (thanks to Gert)

[[Category: RaspberryPi]]
{{Template:RPi_Hardware}}

==Introduction==
[TODO]

==General Purpose Input/Output (GPIO)==
[[File:GPIOs.png|thumb|254px|right|the layout of the Rpi GPIO's, colour coded to the table. [https://sites.google.com/site/burngatehouse/home/drawings/GPIOs.gif Source] ]]

General Purpose Input/Output (a.k.a. GPIO) is a generic pin on a chip whose behavior (including whether it is an input or output pin) can be controlled (programmed) through software.

The Rpi allows peripherals and expansion boards (such as the upcoming [[Rpi Gertboard]]) to access the CPU by exposing the in and outputs.

For further general information about GPIOs, see:[http://en.wikipedia.org/wiki/GPIO the wikipedia article].

The production Raspberry Pi board has a 26-pin 2.54mm (100mil)<ref>http://www.raspberrypi.org/forum/features-and-requests/easy-gpio-hardware-software/page-3/#p31907</ref> expansion header, arranged in a 2x13 strip. They provide 8 GPIO pins plus access to I2C, SPI, UART), as well as +3V3, +5V and GND supply lines. Pin one is the pin in the first column and on the bottom row. <ref>http://www.raspberrypi.org/archives/384</ref>

GPIO voltage levels are 3v3 and are not 5v tolerant. There is no over-voltage protection on the board - the intention is that people interested in serious interfacing will use an external board with buffers, level conversion and analog I/O rather than soldering directly onto the main board.

On the production board, all the UART, SPI and I2C pins can be reconfigured as GPIO pins, to provide a total of 17 GPIO pins<ref>http://www.raspberrypi.org/archives/384</ref>. Each of their functions and full details of how to access are detailed in the chipset datasheet <ref>http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf</ref>.

Each GPIO can interrupt, high/low/rise/fall/change.<ref>http://www.raspberrypi.org/archives/384#comment-5217</ref><ref>http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf</ref>

The availabile alternative functions and their corresponding pins are detailed below. These numbers are in reference to the chipset documentation and may not match the numbers exposed in linux. Only fully usable functions are detailed, for some alternative functions not all the necessary pins are available for the funtionality to be actually used.

The source and sink ability is configurable see [http://www.scribd.com/doc/91353537/GPIO-Pads-Control GPIO Datasheet Addendum - GPIO Pads Control], particular attention should be applied to the note regarding SSO (Simultaneous Switching Outputs). To avoid interference driving currents should be kept as low as possible.

There is also some information on the [[RPi Tutorial Easy GPIO Hardware & Software | Tutorial on Easy GPIO Hardware & Software]].

Kernel boot messages go to the [[RPi_Serial_Connection|UART]] at 115200bps.

'''Header Pinout, top row:'''
{| border="1" style="text-align:center;"
| '''Pin Name''' || '''Pin Function''' || '''Hardware Notes''' || '''General Notes''' || '''Alternative Functions'''
|-
| P1-02 || bgcolor="red" | 5V0
|-
| P1-04 || DNC
|-
| P1-06 || bgcolor="black" | GND
|-
| P1-08 || bgcolor="yellow" | UART0_TXD || || (BCM2835 GPIO14-ALT0) || GPIO14-ALT5 is UART1_TXD, GPIO14
|-
| P1-10 || bgcolor="yellow" | UART0_RXD || || (BCM2835 GPIO15-ALT0) || GPIO15-ALT5 is UART1_RXD, GPIO15
|-
| P1-12 || bgcolor="lime" | BCM2835 GPIO18 || || || GPIO18-ALT5 is PWM0
|-
| P1-14 || DNC
|-
| P1-16 || bgcolor="lime" | BCM2835 GPIO23
|-
| P1-18 || bgcolor="lime" | BCM2835 GPIO24
|-
| P1-20 || DNC
|-
| P1-22 || bgcolor="lime" | BCM2835 GPIO25
|-
| P1-24 || bgcolor="purple" | SPI_CE0_N || || (BCM2835 GPIO8-ALT0) || GPIO08
|-
| P1-26 || bgcolor="purple" | SPI_CE1_N || || (BCM2835 GPIO7-ALT0) || GPIO08
|}

'''Header Pinout, bottom row:'''
{| border="1" style="text-align:center;"
| '''Pin Name''' || '''Pin Function''' || '''Hardware Notes''' || '''General Notes''' || '''Alternative Functions'''
|-
| P1-01 || bgcolor="orange" | 3V3
|-
| P1-03 || bgcolor="cyan" | I2C0_SDA || 1K8 pull up resistor || (BCM2835 GPIO0-ALT0) || GPIO00
|-
| P1-05 || bgcolor="cyan" | I2C0_SCL || 1K8 pull up resistor || (BCM2835 GPIO1-ALT0) || GPIO01
|-
| P1-07 || bgcolor="lime" | GPCLK0 || || (BCM2835 GPIO4-ALT0) || GPIO04-ALT5 is ARM_TDI, GPIO4
|-
| P1-09 || DNC
|-
| P1-11 || bgcolor="lime" | BCM2835 GPIO17 || || ||| GPIO17_ALT3 is UART0_RTS
|-
| P1-13 || bgcolor="lime" | BCM2835 GPIO21
|-
| P1-15 || bgcolor="lime" | BCM2835 GPIO22
|-
| P1-17 || DNC
|-
| P1-19 || bgcolor="purple" | SPI_MOSI || || (BCM2835 GPIO10-ALT0) || GPIO10
|-
| P1-21 || bgcolor="purple" | SPI_MISO || || (BCM2835 GPIO09-ALT0) || GPIO09
|-
| P1-23 || bgcolor="purple" | SPI_SCLK || || (BCM2835 GPIO11-ALT0) || GPIO11
|-
| P1-25 || DNC
|}

{| border="1"
! Colour legend
|-
| bgcolor="red" | +5V
|-
| bgcolor="orange" | +3.3V
|-
| Do not connect
|-
| bgcolor="yellow" | UART
|-
| bgcolor="lime" | GPIO
|-
| bgcolor="purple" | SPI
|-
| bgcolor="cyan" | I2C
|}

KiCad symbol: [[File:Conn-raspberry.lib]]

<ref>http://www.raspberrypi.org/forum/projects-and-collaboration-general/gpio-header-pinout-clarification/page-2</ref>

Pin 3 (SDA0) and Pin 5 (SCL0) are preset to be used as I2C interface. So there are 1K8 pulls up resistors on the board for these pins.<ref>http://www.raspberrypi.org/forum/features-and-requests/easy-gpio-hardware-software/page-6/#p56480</ref>

Pin 12 supports PWM.

It is also possible to reconfigure GPIO connector pins P1-7, 15, 16, 18, 22 (chipset GPIOs 4 and 22 to 25) to provide an ARM JTAG interface.<ref>http://www.raspberrypi.org/forum?mingleforumaction=viewtopic&t=1288.1</ref> However ARM_TMS isn't available on the GPIO connector (chipset pin 12 or 27 is needed). Chipset pin 27 is available on S5, the CSI camera interface however.

It is also possible to reconfigure GPIO connector pins P1-12 and 13 (chipset GPIO 18 and 21) to provide an I2S (hardware mod may be required<ref name="I2S">[http://www.raspberrypi.org/forum/features-and-requests/sad-about-removal-of-i2s-why-was-this-change-made Forum:Sad about removal of I2S. Why was this change made?]</ref>) or PCM interface.<ref>http://www.raspberrypi.org/forum?mingleforumaction=viewtopic&t=1288.2</ref> However, PCM_FS and PCM_DIN (chipset pins 19 and 20) are needed for I2S or PCM.

A second I2C interface (GPIO02_ALT0 is SDA1 and GPIO03_ALT0 is SCL1) and two further GPIOs (GPIO05_ALT0 is GPCLK1, and GPIO27) are available on S5, the CSI camera interface.

===A note about GPIO vs the schematic===

You may notice that the GPIO connector as documented in the schematic does NOT match with what is on this wiki page. Do NOT update this wiki page. The pins which are marked as DNC should not be used in order to be compatible with possible future designs. The plan is that if a new design comes along and if the layout permits it we will connect additional GPIO pins to those DNC pins. (Gert's first vote is for GPIO 19 and 20, That gives us the second PWM, second SPI and I2S)

===Referring to pins on the Expansion header===

The header is referred to as "The GPIO Connector (P1)". To avoid nomenclature confusion between Broadcom signal names on the SoC and pin names on the expansion header, the following naming is highly recommended:

* The expansion header is referred to as "Expansion Header" or "GPIO Connector (P1)"
* Pins on the GPIO connector (P1) are referred to as P1-01, etc.
* Names GPIO0, GPIO1, GPIOx-ALTy, etc refer to the signal names on the SoC as enumerated in the Broadcom datasheet, where "x" matches BCM2835 number (without leading zero) and "y" is the alternate number column 0 to 5 on page 102-103 of the Broadcom document. For example, depending on what you are describing, use either "GPIO7" to refer to a row of the table, and "GPIO7-ALT0" would refer to a specific cell of the table.
* When refering to signal names, you should modify the Broadcom name slightly to minimize confusion. The Broadcom SPI bus pin names are fine, such as "SPI0_*" and "SPI1_*", but they didn't do the same on the I2C and UART pins. Instead of using "SDA0" and "SCL0", you should use "I2C0_SDA" and "I2C0_SCL"; and instead of "TX" or "TXD" and "RX" or "RXD", you should use "UART0_TXD" and "UART0_RXD".

===Power pins===
Maximum permitted current draw from the 3v3 pin is 50mA.

Maximum permitted current draw from the 5v pin is the USB input current (usually 1A) minus any current draw from the rest of the board.<ref>http://www.raspberrypi.org/forum?mingleforumaction=viewtopic&t=1536#postid-21841</ref>
*Model A: 1000mA - 500mA -> max power draw: 500mA
*Model B: 1000mA - 700mA -> max power draw: 300mA

=== GPIO hardware hacking ===

The complete list of chipset GPIO pins which are available on the GPIO connector is: <pre>0, 1, 4, 7, 8, 9, 10, 11, 14, 15, 17, 18, 21, 22, 23, 24, 25</pre>

As noted above, GPIO00 and 01 (SDA0 and SCL0) have 1K8 pull-up resistors to 3v3.

If 17 GPIOs aren't sufficient for your project, there are a few other signals potentially available, with varying levels of software and hardware (soldering iron) hackery skills:

GPIO02, 03, 05 and 27 are available on S5 (the CSI interface) when a camera peripheral is not connected to that socket, and are configured by default to provide the functions SDA1, SCL1, CAM_CLK and CAM_GPIO respectively. SDA1 and SCL1 have 1K6 pull-up resistors to 3v3.

GPIO06 is LAN_RUN and is available on pad 12 of the footprint for IC3 on the Model A. On Model B, it is in use for the Ethernet function.

There are a few other chipset GPIO pins accessible on the PCB but are in use:

GPIO16 drives status LED D5 (usually SD card access indicator)
GPIO28-31 are used by the board ID and are connected to resistors R3 to R10.
GPIO40 and 45 are used by analogue audio and support PWM. They connect to the analogue audio circuitry via R21 and R27 respectively.
GPIO46 is HDMI hotplug detect (goes to pin 6 of IC1).
GPIO47 to 53 are used by the SD card interface. In particular, GPIO47 is SD card detect (this would seem to be a good candidate for re-use). GPIO47 is connected to the SD card interface card detect switch; GPIO48 to 53 are connected to the SD card interface via resistors R45 to R50.

===Driver support===

The Foundation will not include a GPIO driver in the initial release, standard linux GPIO drivers should work with minimal modification.<ref>http://www.raspberrypi.org/forum?mingleforumaction=viewtopic&t=1278.0</ref>
The Foundation will not include an SPI driver in the initial release, we hope the community might write one.<ref>http://www.raspberrypi.org/forum?mingleforumaction=viewtopic&t=1278.0</ref>
The Foundation will not include an I2C driver in the initial release, we hope the community might provide one, standard linux I2C drivers should work with minimal modification.<ref>http://www.raspberrypi.org/forum?mingleforumaction=viewtopic&t=1202</ref>

===Code examples===
====GPIO Driving Example (C)====
[http://www.raspberrypi.org/forum/educational-applications/gertboard/page-4/#p31555 Gert van Loo & Dom, has provided] some tested code which accesses the GPIO pins through direct GPIO register manipulation in C-code.
(Thanks to Dom for doing the difficult work of finding and testing the mapping.)
Example GPIO code:

<pre>
//
// How to access GPIO registers from C-code on the Raspberry-Pi
// Example program
// 15-January-2012
// Dom and Gert
//

// Access from ARM Running Linux

#define BCM2708_PERI_BASE 0x20000000
#define GPIO_BASE (BCM2708_PERI_BASE + 0x200000) /* GPIO controller */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <dirent.h>
#include <fcntl.h>
#include <assert.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <unistd.h>

#define PAGE_SIZE (4*1024)
#define BLOCK_SIZE (4*1024)

int mem_fd;
char *gpio_mem, *gpio_map;
char *spi0_mem, *spi0_map;

// I/O access
volatile unsigned *gpio;

// GPIO setup macros. Always use INP_GPIO(x) before using OUT_GPIO(x) or SET_GPIO_ALT(x,y)
#define INP_GPIO(g) *(gpio+((g)/10)) &= ~(7<<(((g)%10)*3))
#define OUT_GPIO(g) *(gpio+((g)/10)) |= (1<<(((g)%10)*3))
#define SET_GPIO_ALT(g,a) *(gpio+(((g)/10))) |= (((a)<=3?(a)+4:(a)==4?3:2)<<(((g)%10)*3))

#define GPIO_SET *(gpio+7) // sets bits which are 1 ignores bits which are 0
#define GPIO_CLR *(gpio+10) // clears bits which are 1 ignores bits which are 0

void setup_io();

int main(int argc, char **argv)
{ int g,rep;

// Set up gpi pointer for direct register access
setup_io();

// Switch GPIO 7..11 to output mode

/************************************************************************\
* You are about to change the GPIO settings of your computer. *
* Mess this up and it will stop working! *
* It might be a good idea to 'sync' before running this program *
* so at least you still have your code changes written to the SD-card! *
\************************************************************************/

// Set GPIO pins 7-11 to output
for (g=7; g<=11; g++)
{
INP_GPIO(g); // must use INP_GPIO before we can use OUT_GPIO
OUT_GPIO(g);
}

for (rep=0; rep<10; rep++)
{
for (g=7; g<=11; g++)
{
GPIO_SET = 1<<g;
sleep(1);
}
for (g=7; g<=11; g++)
{
GPIO_CLR = 1<<g;
sleep(1);
}
}

return 0;

} // main

//
// Set up a memory regions to access GPIO
//
void setup_io()
{

/* open /dev/mem */
if ((mem_fd = open("/dev/mem", O_RDWR|O_SYNC) ) < 0) {
printf("can't open /dev/mem \n");
exit (-1);
}

/* mmap GPIO */

// Allocate MAP block
if ((gpio_mem = malloc(BLOCK_SIZE + (PAGE_SIZE-1))) == NULL) {
printf("allocation error \n");
exit (-1);
}

// Make sure pointer is on 4K boundary
if ((unsigned long)gpio_mem % PAGE_SIZE)
gpio_mem += PAGE_SIZE - ((unsigned long)gpio_mem % PAGE_SIZE);

// Now map it
gpio_map = (unsigned char *)mmap(
(caddr_t)gpio_mem,
BLOCK_SIZE,
PROT_READ|PROT_WRITE,
MAP_SHARED|MAP_FIXED,
mem_fd,
GPIO_BASE
);

if ((long)gpio_map < 0) {
printf("mmap error %d\n", (int)gpio_map);
exit (-1);
}

// Always use volatile pointer!
gpio = (volatile unsigned *)gpio_map;

} // setup_io

</pre>

====GPIO Pull Up/Pull Down Register Example====
<pre>
// enable pull-up on GPIO24&25
GPIO_PULL = 2;
short_wait();
// clock on GPIO 24 & 25 (bit 24 & 25 set)
GPIO_PULLCLK0 = 0x03000000;
short_wait();
GPIO_PULL = 0;
GPIO_PULLCLK0 = 0;
</pre>

====GPIO Driving Example (Python)====
This uses the Python module available at http://pypi.python.org/pypi/RPi.GPIO
* Disclaimer: Untested !
<pre>
import RPi.GPIO as GPIO

# set up the GPIO channels - channel 0 (input) and channel 1 (output)
GPIO.setup(0, GPIO.IN)
GPIO.setup(1, GPIO.OUT)

# input from channel 0 - note that input_value will be a boolean
input_value = GPIO.input(0)

# output True to channel 1. NB you can use '1', 1 or anything that evaluates to True/False
GPIO.output(1, True)
</pre>

====GPIO Driving Example (Shell script)====
* Disclaimer: Untested !
<pre>
#!/bin/sh

# GPIO numbers should be from this list
# 0, 1, 4, 7, 8, 9, 10, 11, 14, 15, 17, 18, 21, 22, 23, 24, 25

# set up GPIO 4 and set to output
echo "4" > /sys/class/gpio/export
echo "out" > /sys/class/gpio/gpio4/direction

# set up GPIO 7 and set to input
echo "7" > /sys/class/gpio/export
echo "in" > /sys/class/gpio/gpio7/direction

# write output
echo "1" > /sys/class/gpio/gpio4/value

# read from input
cat /sys/class/gpio/gpio7/value

# clean up
echo "4" > /sys/class/gpio/unexport
echo "7" > /sys/class/gpio/unexport
</pre>

==MIPI CSI-2==

On the production board, we bring out the MIPI CSI-2 interface to a 15-way flat flex connector

is Sony sub-LVDS same as MIPI CSI-2? Sony IMX020 5Mbip module is available for $5-7 (SE K850i replacement camera).

Looks like Nokia N95 uses CSI-2 5Mpix camera module with autofocus. ~$15 replacement part.

==DSI==

On the production board, we bring out the DSI interface to a 15-way flat flex connector.

==CEC==

[[CEC (Consumer Electronics Control) over HDMI|HDMI-CEC (Consumer Electronics Control for HDMI)]] is supported by hardware but some driver work will be needed and currently isn't exposed into Linux userland.
Eben notes that he has seen CEC demos on the Broadcom SoC they are using.

For more information about HDMI-CEC and what you could do with it on the Raspberry Pi please see the [[CEC (Consumer Electronics Control) over HDMI]] article.

== References ==
<references/>

{{Template:Raspberry Pi}}

RPi Documentation

2012-04-26T10:21:36Z

Meltwater: /* Additional Published Information */

{{Template:RPi Resources}}

Note: All datasheets, documents and Trademarks remain the property of their respective owners.

=Published Datasheets=
==User Guides==
[http://elinux.org/File:Raspi-Model-AB-Mono-2-699x1024.png Raspberry Pi Model A/Model B Layout Diagram]
==Hardware / Software Datasheets==
===Raspberry Pi Processor Broadcom System-On-Chip:===
[http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf BCM2835 ARM Peripherals] - ([[BCM2835 datasheet errata]])

[http://www.scribd.com/doc/91353537/GPIO-Pads-Control GPIO Datasheet Addendum - GPIO Pads Control]

===ARM 11 CPU Core:===
[http://infocenter.arm.com/help/topic/com.arm.doc.ddi0301h/DDI0301H_arm1176jzfs_r0p7_trm.pdf (ARM1176JZF-S)]

===Model B LAN Chip:===
[http://www.smsc.com/media/Downloads_Public/Data_Briefs/9512db.pdf (LAN9512) Data Brief] | [http://www.smsc.com/media/Downloads_Public/Data_Sheets/9512.pdf (LAN9512) Datasheet])

==Mechanical Data==
===Production Boards (2012 Q1):===
none available yet
===Beta Boards:===
[http://www.scribd.com/doc/77785093/Raspberry-Pi-initial-Beta-boards-Mechanical Gert's Beta Boards Mechanical Data]

==Schematics==
===Production Boards (2012 Q1):===
none available yet
===Beta Boards:===
[http://www.raspberrypi.org/wp-content/uploads/2011/11/gerbers2.png Beta Board PCB Layers Screenshot]

[http://lh3.googleusercontent.com/-uO4l8pwSLvU/TsQGbth6x6I/AAAAAAAAAkk/5zQMH3uKPiE/s829/Boardlayout.png Beta Board PCB Layers Screenshot, labelled version]

=Additional Published Information=
==Gert Board:==
[http://www.scribd.com/doc/88286916/Gertboard-Overview Gertboard-Overview]

==Power Supply Details:==
[http://www.scribd.com/doc/69700160/Rasp-Why-Does-It-Use-More-Power Detailed explanation of the Beta board power supply]

[http://www.raspberrypi.org/wp-content/uploads/2011/12/psu.png Preliminary power supply schematic, Beta board]

=Documentation Projects=
==Frambozenier.org Datasheets:==
[[RPi DatasheetCategories | Frambozenier.org Documentation Project Datasheets]] - Selection of detailed datasheets on the Raspberry Pi (developed on the wiki, reviewed then published).

{{Template:Raspberry Pi}}

RPi Documentation

2012-04-26T10:19:42Z

Meltwater: /* Hardware / Software Datasheets */

{{Template:RPi Resources}}

Note: All datasheets, documents and Trademarks remain the property of their respective owners.

=Published Datasheets=
==User Guides==
[http://elinux.org/File:Raspi-Model-AB-Mono-2-699x1024.png Raspberry Pi Model A/Model B Layout Diagram]
==Hardware / Software Datasheets==
===Raspberry Pi Processor Broadcom System-On-Chip:===
[http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf BCM2835 ARM Peripherals] - ([[BCM2835 datasheet errata]])

[http://www.scribd.com/doc/91353537/GPIO-Pads-Control GPIO Datasheet Addendum - GPIO Pads Control]

===ARM 11 CPU Core:===
[http://infocenter.arm.com/help/topic/com.arm.doc.ddi0301h/DDI0301H_arm1176jzfs_r0p7_trm.pdf (ARM1176JZF-S)]

===Model B LAN Chip:===
[http://www.smsc.com/media/Downloads_Public/Data_Briefs/9512db.pdf (LAN9512) Data Brief] | [http://www.smsc.com/media/Downloads_Public/Data_Sheets/9512.pdf (LAN9512) Datasheet])

==Mechanical Data==
===Production Boards (2012 Q1):===
none available yet
===Beta Boards:===
[http://www.scribd.com/doc/77785093/Raspberry-Pi-initial-Beta-boards-Mechanical Gert's Beta Boards Mechanical Data]

==Schematics==
===Production Boards (2012 Q1):===
none available yet
===Beta Boards:===
[http://www.raspberrypi.org/wp-content/uploads/2011/11/gerbers2.png Beta Board PCB Layers Screenshot]

[http://lh3.googleusercontent.com/-uO4l8pwSLvU/TsQGbth6x6I/AAAAAAAAAkk/5zQMH3uKPiE/s829/Boardlayout.png Beta Board PCB Layers Screenshot, labelled version]

=Additional Published Information=

==Power Supply Details:==
[http://www.scribd.com/doc/69700160/Rasp-Why-Does-It-Use-More-Power Detailed explanation of the Beta board power supply]

[http://www.raspberrypi.org/wp-content/uploads/2011/12/psu.png Preliminary power supply schematic, Beta board]

=Documentation Projects=
==Frambozenier.org Datasheets:==
[[RPi DatasheetCategories | Frambozenier.org Documentation Project Datasheets]] - Selection of detailed datasheets on the Raspberry Pi (developed on the wiki, reviewed then published).

{{Template:Raspberry Pi}}