BeagleBoardUbuntu

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Revision as of 10:16, 27 January 2014 by RobertCNelson (talk | contribs) (DSP: drop dsp section... no one is working on it, bitrotten/etc...)
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(For BeagleBoardAngstrom, click here.)

This page is about running a Linux distribution (ARM EABI) Ubuntu on the BeagleBoard. BeagleBoard will boot the (ARM EABI) Ubuntu distribution from the SD card. Since much of this page is generic, it has also been extended to help support devices such as the PandaBoard and BeagleBone.

  • For the best experience, make sure you have an LCD/HDMI monitor attached to the BeagleBoard's HDMI port, 2 GB/4 GB/8 GB SD card, and a known good USB 2.0 hub with mouse and keyboard.

Help

If you need any help:

  • Ubuntu related help:
    • #ubuntu-arm: Ubuntu's ARM IRC on Freenode (logs -> year -> month -> day -> #ubuntu-arm.html)
  • When requesting help, please provide some debugging information:
    • U-Boot Version installed on board
    • Kernel Version: uname -a
    • pastebin dmesg
      • Copy from serial port or use "dmesg | pastebinit" (sudo apt-get install pastebinit)

Required Beagle Software

Mainline U-Boot:

  • All older BeagleBoard (classic) Ax, Bx, Cx and Dx boards are required to upgrade to at least these U-Boot versions
  • XM Boards have no NAND, so MLO/u-boot.img is always required on the first partition
  • Directions: Upgrade X-loader and U-Boot

Omap Serial Changes

boot.scr/boot.cmd changes:

With 2.6.35:

console=ttyS2,115200n8

With 2.6.36/37+:

console=ttyO2,115200n8

Serial console login: /etc/init/ttyO2.conf

start on stopped rc RUNLEVEL=[2345]
stop on runlevel [!2345]

respawn
exec /sbin/getty 115200 ttyO2


Method 1: Download a Complete Pre-Configured Image

Demo Image

  • These demonstration images contain a custom Mainline based kernel with experimental enhancements to the boards supported. They are usually updated about once a month, as new features/enhancements get added by the community. Currently, this image ships with two kernels "armv7" which is for mainline omap3+ devices (BeagleBoard/PandaBoard) and the "bone" which is specifically for the BeagleBone. The kernel is stress-tested by a farm of Panda/Beagles running 24/7 under a heavy load (building gcc trunk/mainline kernel).
git clone git://github.com/RobertCNelson/armv7-multiplatform.git
cd armv7-multiplatform
git checkout origin/v3.13.x -b tmp
./build_kernel.sh
git clone git://github.com/RobertCNelson/linux-dev.git
cd linux-dev
git checkout origin/am33x-v3.8 -b tmp
./build_kernel.sh
  • Advanced Users only: Userspace, used in these demo images:
https://github.com/RobertCNelson/omap-image-builder

If the script in these demo images fail: email "bugs@rcn-ee.com" I will need details: terminal command, terminal log, distribution name, arch...

Saucy 13.10

Image Updated:

  • 2014-01-24
    • Beagle/Beagle xM: v3.13.0-armv7-x9 kernel
    • BeagleBone/BeagleBone Black: v3.8.13-bone37 kernel
  • 2013-12-17
    • Beagle xM (ONLY): v3.12.5-armv7-x10 kernel (--dtb dt-beagle-xm)
    • BeagleBone/BeagleBone Black: v3.8.13-bone32 kernel
    • Beagle/Panda/Panda ES: v3.7.10-x13 kernel
  • 2013-11-15
    • Beagle xM (ONLY): v3.12.0-armv7-x8 kernel (--dtb dt-beagle-xm)
    • BeagleBone/BeagleBone Black: v3.8.13-bone30 kernel
      • audio/mmc fixes...
    • Beagle/Panda/Panda ES: v3.7.10-x13 kernel

Services Active:

Note: Depending on your internal network these may work out of the box
Apache, Port 80: http://arm/ (Bone: via usb) http://192.168.7.2
SSH, Port 22: ssh ubuntu@arm (Bone: via usb) ubuntu@192.168.7.2
Getty, Serial Port

Default user: ubuntu pass: temppwd

Get prebuilt image:

wget https://rcn-ee.net/deb/rootfs/saucy/ubuntu-13.10-console-armhf-2014-01-24.tar.xz

Verify Image with:

md5sum ubuntu-13.10-console-armhf-2014-01-24.tar.xz
e199c4c20091abcf1ed025ee54856055  ubuntu-13.10-console-armhf-2014-01-24.tar.xz

Unpack Image:

tar xf ubuntu-13.10-console-armhf-2014-01-24.tar.xz
cd ubuntu-13.10-console-armhf-2014-01-24

If you don't know the location of your SD card:

sudo ./setup_sdcard.sh --probe-mmc

You should see something like:

Are you sure? I don't see [/dev/idontknow], here is what I do see...

fdisk -l:
Disk /dev/sda: 500.1 GB, 500107862016 bytes <- x86 Root Drive
Disk /dev/sdd: 3957 MB, 3957325824 bytes <- MMC/SD card

lsblk:
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 465.8G  0 disk 
├─sda1   8:1    0 446.9G  0 part /  <- x86 Root Partition
├─sda2   8:2    0     1K  0 part 
└─sda5   8:5    0  18.9G  0 part [SWAP]
sdd      8:48   1   3.7G  0 disk 
├─sdd1   8:49   1    64M  0 part 
└─sdd2   8:50   1   3.6G  0 part 
  • In this example, we can see via mount, /dev/sda1 is the x86 rootfs, therefore /dev/sdd is the other drive in the system, which is the MMC/SD card that was inserted and should be used by ./setup_sdcard.sh...

Install Image:

Quick install script for [board]

sudo ./setup_sdcard.sh --mmc /dev/sdX --uboot board

[board] options:

  • BeagleBone/Black - bone

So for the BeagleBone:

sudo ./setup_sdcard.sh --mmc /dev/sdX --uboot bone

Quick install script for [board] (using new --dtb option)

sudo ./setup_sdcard.sh --mmc /dev/sdX --dtb board

board options:

  • BeagleBoard Ax/Bx/Cx/Dx - omap3-beagle
  • BeagleBoard xM - omap3-beagle-xm

So for the BeagleBoard xM:

sudo ./setup_sdcard.sh --mmc /dev/sdX --dtb omap3-beagle-xm

You should now be able to unmount the SD card from your PC, insert into your Board, reboot and have the OS loaded.

For a basic framebuffer driven desktop environment: (make sure network is setup):

Ethernet: sudo ifconfig -a and sudo dhclient usb1 or sudo dhclient eth0
Wireless: http://elinux.org/BeagleBoardUbuntu#Wi-Fi_Networking_.28command_line.29

Then run:

/bin/sh /boot/uboot/tools/ubuntu/small-lxde-desktop.sh

Advanced: Build Image:

Built with a fork of project-rootstock (ARM native mode, runs directly on BeagleBoard), using a script from omap-image-builder:

git clone git://github.com/RobertCNelson/omap-image-builder.git
cd omap-image-builder
git checkout v2014.01-1 -b tmp
touch release
./rcn-ee_image.sh

Raring 13.04

Image Updated:

  • 2014-01-24
    • Beagle/Beagle xM: v3.13.0-armv7-x9 kernel
    • BeagleBone/BeagleBone Black: v3.8.13-bone37 kernel
  • 2013-12-17
    • Beagle xM (ONLY): v3.12.5-armv7-x10 kernel (--dtb dt-beagle-xm)
    • BeagleBone/BeagleBone Black: v3.8.13-bone32 kernel
    • Beagle/Panda/Panda ES: v3.7.10-x13 kernel
  • 2013-11-15
    • Beagle xM (ONLY): v3.12.0-armv7-x8 kernel (--dtb dt-beagle-xm)
    • BeagleBone/BeagleBone Black: v3.8.13-bone30 kernel
      • audio/mmc fixes...
    • Beagle/Panda/Panda ES: v3.7.10-x13 kernel

Get prebuilt image:

wget https://rcn-ee.net/deb/rootfs/raring/ubuntu-13.04-console-armhf-2014-01-24.tar.xz

Verify Image with:

md5sum ubuntu-13.04-console-armhf-2014-01-24.tar.xz
0443f6b38a6a082f5a75f72f8a5cfaf4  ubuntu-13.04-console-armhf-2014-01-24.tar.xz

Unpack image:

tar xf ubuntu-13.04-console-armhf-2014-01-24.tar.xz
cd ubuntu-13.04-console-armhf-2014-01-24

Then follow the directions shown above with the other images...

Trusty 14.04 (experimental)

Image Updated:

  • 2014-01-24
    • Beagle/Beagle xM: v3.13.0-armv7-x9 kernel
    • BeagleBone/BeagleBone Black: v3.8.13-bone37 kernel
  • 2013-12-17
    • Beagle xM (ONLY): v3.12.5-armv7-x10 kernel (--dtb dt-beagle-xm)
    • BeagleBone/BeagleBone Black: v3.8.13-bone32 kernel
    • Beagle/Panda/Panda ES: v3.7.10-x13 kernel
  • 2013-11-15
    • Beagle xM (ONLY): v3.12.0-armv7-x8 kernel (--dtb dt-beagle-xm)
    • BeagleBone/BeagleBone Black: v3.8.13-bone30 kernel
      • audio/mmc fixes...
    • Beagle/Panda/Panda ES: v3.7.10-x13 kernel

Get prebuilt image:

wget https://rcn-ee.net/deb/rootfs/trusty/ubuntu-trusty-console-armhf-2014-01-24.tar.xz

Verify Image with:

md5sum ubuntu-trusty-console-armhf-2014-01-24.tar.xz
ae97d2b7d927685a2bcd15303a1b2766  ubuntu-trusty-console-armhf-2014-01-24.tar.xz

Unpack image:

tar xf ubuntu-trusty-console-armhf-2014-01-24.tar.xz
cd ubuntu-trusty-console-armhf-2014-01-24

Then follow the directions shown above with the other images...

Flasher

eMMC: BeagleBone Black

This image can be written to a 2GB (or larger) microSD card, via 'dd' on linux or the win32 image program linked to on CircuitCo's wiki page. First press and hold the boot select button (next to the microSD card), then apply power (same procedure as the official CircuitCo images). The board should boot into Ubuntu and begin flashing the eMMC, once completed all 4 LED's should be full ON. Simply remove power, remove the microSD card and Ubuntu will now boot directly from eMMC.

Script for reference: (this is the script that writes to the eMMC)

https://github.com/RobertCNelson/tools/blob/master/scripts/beaglebone-black-copy-microSD-to-eMMC.sh

BTW: we are only writing about 500 megabytes to the eMMC, so the script will only take about 5-6 Minutes after power on.

Notes:

  • If only two LED's stay lit and nothing happens, the board has crashed due to lack of power. Retry with a 5Volt DC power supply connected.
  • If the 4 LED's blink a constant pattern, the eMMC write has failed. First REMOVE ALL capes, then retry again.
    • (error -84: which may mean you've reached the max number of erase/write cycles...)

User: ubuntu pass: temppwd

Image Updated:

  • 2014-01-24
    • BeagleBone Black: v3.8.13-bone37 kernel
  • 2013-12-17
    • BeagleBone Black: v3.8.13-bone32 kernel
  • 2013-11-15
    • BeagleBone Black: v3.8.13-bone30 kernel
      • ssh host key fixes (auto generated on bootup...)

Get prebuilt image:

wget https://rcn-ee.net/deb/flasher/saucy/BBB-eMMC-flasher-ubuntu-13.10-2014-01-24-2gb.img.xz

Verify Image with:

md5sum BBB-eMMC-flasher-ubuntu-13.10-2014-01-24-2gb.img.xz
2cce18a56e1802657aad15dc700ec200  BBB-eMMC-flasher-ubuntu-13.10-2014-01-24-2gb.img.xz

Follow the "standard" update procedure.

http://circuitco.com/support/index.php?title=Updating_The_Software

Linux:

unxz BBB-eMMC-flasher-ubuntu-13.10-2014-01-24-2gb.img.xz
sudo dd if=./BBB-eMMC-flasher-ubuntu-13.10-2014-01-24-2gb.img of=/dev/sdX

raw microSD img

BeagleBone/BeagleBone Black

This image can be written to a 2GB (or larger) microSD card, via 'dd' on linux or the win32 image program linked to on CircuitCo's wiki page. First press and hold the boot select button (next to microSD card), then apply power (same procedure as the official CircuitCo images). The board should boot into Ubuntu.

User: ubuntu pass: temppwd

Auto partition resize:

cd /opt/scripts/tools
git pull
./grow_partition.sh
sudo reboot

Image Updated:

  • 2014-01-24
    • BeagleBone/BeagleBone Black: v3.8.13-bone37 kernel
  • 2013-12-17
    • BeagleBone/BeagleBone Black: v3.8.13-bone32 kernel
  • 2013-11-15
    • BeagleBone/BeagleBone Black: v3.8.13-bone30 kernel

Get prebuilt image:

wget https://rcn-ee.net/deb/microsd/saucy/bone-ubuntu-13.10-2014-01-24-2gb.img.xz

Verify Image with:

md5sum bone-ubuntu-13.10-2014-01-24-2gb.img.xz
c53ab3fb2f97951a1e1fb60c8719ae55  bone-ubuntu-13.10-2014-01-24-2gb.img.xz

Linux:

unxz bone-ubuntu-13.10-2014-01-24-2gb.img.zx
sudo dd if=./bone-ubuntu-13.10-2014-01-24-2gb.img of=/dev/sdX

Method 2: Use the NetInstall method

You will need a 1GB/2GB/4GB/8GB SD card or greater.

Standard system : ~700 MB

Report Bugs/Issues to: https://github.com/RobertCNelson/netinstall/issues (anywhere else will be ignored..)

Download the netinstall script:

git clone git://github.com/RobertCNelson/netinstall.git
cd netinstall

Currently supported Ubuntu distributions:

--distro oneiric (11.10)
--distro precise-armhf (12.04)
--distro quantal (12.10)
--distro raring (13.04)
--distro saucy (13.10)

Device: <board> selection:

*BeagleBoard Ax/Bx/Cx  - omap3-beagle
*BeagleBoard xMA/B/C   - omap3-beagle-xm
*BeagleBone Ax         - am335x-bone-serial
*BeagleBone (DVI cape) - am335x-bone-video
*BeagleBone Black      - am335x-boneblack
*PandaBoard Ax     - omap4-panda
*PandaBoard A4+    - omap4-panda-a4
*PandaBoard ES     - omap4-panda-es

Installation script for new <board> selection: (slowly migrating all devices to this method)

sudo ./mk_mmc.sh --mmc /dev/sdX --dtb <board> --distro <distro>

So for the xM: with quantal:

sudo ./mk_mmc.sh --mmc /dev/sdX --dtb omap3-beagle-xm --distro quantal
  • Other Options:
    • --firmware : installs firmware
    • --serial-mode : debian-installer uses Serial Port

Place SD card into BeagleBoard and boot:

Configure the network:

usb0: USB net <- (usually the OTG port)
eth0: USB net <- (usually the smsc95xx adapter on the BeagleBoard and PandaBoard)
wlan0: Wifi <- Your USDB-Wi-Fi device.. 

See my notes for my testing procedure: https://github.com/RobertCNelson/netinstall/blob/master/test.Ubuntu

Troubleshooting: If booting fails..

  • Hold the user button down to force booting from MMC
  • Upgrade X-loader and U-boot Upgrade X-loader and U-Boot
  • Clear U-boot's Environment Variables in NAND:
nand erase 260000 20000

NetInstall assumptions:

Assume asll <default>'s... Thanks you preseed.conf!!!

Method 3: Manual Install (no automatic scripts)

Note, this section used to have a lot of details, but maintenance of the two wiki's became a pain, so for now on we will just link to my other pages:

Beagle/Beagle xM

http://eewiki.net/display/linuxonarm/BeagleBoard

BeagleBone

http://eewiki.net/display/linuxonarm/BeagleBone

Panda/Panda ES

http://eewiki.net/display/linuxonarm/PandaBoard

Advanced

Install Latest Kernel Image

Script:

cd /opt/scripts/tools
git pull

Stable:

./update_kernel.sh

Testing:

./update_kernel.sh --beta-kernel

Custom: (has to be on rcn-ee.net)

./update_kernel.sh --kernel v3.8.13-bone37

Reboot with your new Kernel Image.

Upgrade X-loader and U-boot

  • Note: the functionality of the "X-Loader" project has been merged as u-boot spl.

Compatibility with older Ax, Bx, Cx, and Dx BeagleBoards

Note: Sometimes on these older boards, you just have to clear out the stored U-Boot environment variables in NAND to make this script work:

nand erase 260000 20000

Or: To fully erase the entire NAND:

nand erase.chip

Requires MMC card:

git clone git://github.com/RobertCNelson/flasher.git
cd flasher

For the Beagle Ax/Bx

sudo ./mk_mmc.sh --mmc /dev/sdX --uboot beagle_bx

For the Beagle Cx/Dx

sudo ./mk_mmc.sh --mmc /dev/sdX --uboot beagle_cx
1: Plug-in a serial cable and start the serial terminal program
2: Place MMC card in Beagle
3: Push and hold the user button
4: Plug-in power
5: Wait for U-Boot countdown to finish, then release the user button
6: Wait for flashing/script to end
7: Power down, remove and reformat MMC card to final OS

If you don't know the location of your SD card:

sudo ./mk_mmc.sh --probe-mmc

You should see something like:

Are you sure? I don't see [/dev/idontknow], here is what I do see...

fdisk -l:
Disk /dev/sda: 500.1 GB, 500107862016 bytes <- x86 Root Drive
Disk /dev/mmcblk0: 3957 MB, 3957325824 bytes <- MMC/SD card

mount:
/dev/sda1 on / type ext4 (rw,errors=remount-ro,commit=0) <- x86 Root Partition
  • In this example, we can see via mount, /dev/sda1 is the x86 rootfs, therefore /dev/mmcblk0 is the other drive in the system, which is the MMC/SD card that was inserted and should be used by the ./mk_mmc.sh script.

SGX Video Acceleration

BeagleBone (BBW) & BeagleBone Black (BBB)

SGX support will most likely be included with Kernel 3.12 (see TI Graphics SDK release 5.01.00.01), which is being worked on now (January 2014).

Xorg omapfb Drivers

By default Ubuntu will try to use the FBDEV video driver, however for the BeagleBoard we can take advantage of a more software optimized driver (still not using the sgx video hardware) using the NEON extensions of the Cortex-A8 core.

cat /var/log/Xorg.0.log | grep FBDEV

(II) FBDEV: driver for framebuffer: fbdev
(II) FBDEV(0): using default device
(II) FBDEV(0): Creating default Display subsection in Screen section
(==) FBDEV(0): Depth 16, (==) framebuffer bpp 16
(==) FBDEV(0): RGB weight 565

Login into Ubuntu and open a new terminal, xorg has to be running:

xvinfo -display :0.0

X-Video Extension version 2.2
screen #0
 no adaptors present

Drivers

Note: These are built with neon optimizations: http://git.debian.org/?p=collab-maint/xf86-video-omapfb.git;a=blob;f=debian/rules;h=c2f0d5391c96c5abb60b1e691ad86bb27e0c17d8;hb=HEAD (line 48/49)

Lucid:

sudo apt-get install xserver-xorg-video-omap3

To verify it was correctly installed, reboot and:

cat /var/log/Xorg.0.log | grep omapfb

(II) LoadModule: "omapfb"
(II) Loading /usr/lib/xorg/modules/drivers//omapfb_drv.so
(II) Module omapfb: vendor="X.Org Foundation"
(II) omapfb: Driver for OMAP framebuffer (omapfb) and external LCD controllers:
(WW) Error opening /sys/devices/platform/omapfb/ctrl/name: No such file or directory
(II) omapfb(0): VideoRAM: 1800KiB (SDRAM)
(II) omapfb(0): Creating default Display subsection in Screen section
(**) omapfb(0): Depth 16, (--) framebuffer bpp 16
(==) omapfb(0): RGB weight 565
(==) omapfb(0): Default visual is TrueColor
(--) omapfb(0): Virtual size is 1280x720 (pitch 1280)
(**) omapfb(0):  Built-in mode "current"
(==) omapfb(0): DPI set to (96, 96)
(II) omapfb(0): DPMS enabled
(II) omapfb(0): Video plane capabilities:
(II) omapfb(0): Video plane supports the following image formats:
(II) omapfb(0): XVideo extension initialized

Login into Ubuntu and open a new terminal, xorg has to be running:

xvinfo -display :0.0

X-Video Extension version 2.2
screen #0
  Adaptor #0: "OMAP XV adaptor"
    number of ports: 1
    port base: 56
    operations supported: PutImage 
    supported visuals:
      depth 16, visualID 0x21
    number of attributes: 1
    etc..

Changing DVI output resolution

Ubuntu 10.10 above defaults to a resolution of 1284x768@16. This is set in the boot.cmd file in the boot partition of the SD card. To change the resolution the DVI output, edit boot.cmd accordingly, then recreate the boot.scr file by:

mkimage -A arm -O linux -T script -C none -a 0 -e 0 -n "Ubuntu 10.10" -d ./boot.cmd ./boot.scr

Then reboot the BeagleBoard.

S-Video

(For details on configuring S-Video on Angstrom, click here).

Process for setting up S-Video

S-video is tested to be working on 2.6.35-rc5-dl9. BeagleBoard s-video output has traditionally been enabled by "using bootargs (boot arguments) at uboot". In newer versions of the BeagleBoard, the developers have made things easier by instructing U-Boot to look for a .scr file about a dozen lines long that is called cmd.boot.scr, and then follow said parameters. In Angstrom, no boot.scr file is needed, instead, an even easier system is used, where a simple editable .txt file called uEnv.txt containing these parameters suffices (Env is for "environment"). For some reason, in the Ubuntu download files, typically there is a bit of convoluted process where uEnv.txt is called up, uEnv.txt says "Go read conf.boot.scr", and cmd.boot.scr sets up the s-video.

To make cmd.boot.scr, create a text file named cmd.boot, then convert it into a .scr file with mkimage by running the following commands on the terminal:

First, you will probably need to get mkimage with apt-get. Run

   sudo apt-get install mkimage

Next, convert your cmd.boot.scr:

   mkimage -A arm -O linux -T script -C none -a 0 -e 0 -n 'Execute uImage' -d boot.cmd boot.scr

Bootargs: make this cmd.boot to set s-video

  • NTSC
    omapfb.mode=tv:ntsc 
    omapdss.def_disp=tv

Bootargs that have been validated:

    setenv bootargs 'console=tty0 console=ttyO2,115200n8 root=/dev/mmcblk0p2 rootwait ro vram=12M omapfb.mode=tv:ntsc omapdss.def_disp=tv 
    fixrtc buddy=unknown'

Screen cutoff problem

NTSC resolution is supposed to be 640x480. However the edge bands around the TV screen differ from TV to TV. Output of fbset shown below:

   mode "720x482-30"
        # D: 13.500 MHz, H: 15.734 kHz, V: 29.970 Hz
        geometry 720 482 720 482 32
        timings 74074 16 58 6 31 64 6
        rgba 8/16,8/8,8/0,0/0
   endmode

Depending on your TV device, and what desktop you are running a certain amount of screen cutoff is likely to occur. This is called overscan. Typically, around 5-10% of the left and right edges of display are off the screen (using Ubuntu with xfce). This seems to be due to the fact that there is only one display resolution that is set for NTSC: 720 X 482. It is not possible to change this setting in the xfce4 Settings Manager like one would normally be able to do, because other options are greyed out/do not exist. Normally, even if the Settings Manager did not allow for it, a different resolution setting could be obtained by editing the xorg.conf file in /etc/X11/xorg.conf-4, or some similar place. HOWEVER there is no xorg.conf file in the Beagle version of xfce. xrandr shows the display is set to the minimum of 720x574. Adding an xorg.conf does not fix the problem, because Beagle takes its (analog) display resolution settings directly from the display driver, where 720 X 480 (720 X 574 for PAL ) is hard-coded in.

An inelegant but usable workaround for the xfce desktop environment is simply to create vertical and horizontal panels that fill up the space that is cut off on the screen. This is not a complete solution, but at least it will prevent maximized windows from going off into nowhere land.

Truly fixing this would involve going into the display driver and reprogramming it to include additional S-video settings other than just NTSC and PAL. Specifically, to make the entire framebuffer fit on the screen you would need to adjust the overlay in the display driver, the OMAP DSS2. (Didn't test this yet. Some pointers from the driver's documentation below)

   /sys/devices/platform/omapdss/overlay? directory:
   enabled		0=off, 1=on
   input_size		width,height (ie. the framebuffer size)
   manager		Destination overlay manager name
   name
   output_size		width,height
   position		x,y
   screen_width	width
   global_alpha   	global alpha 0-255 0=transparent 255=opaque

Building the Kernel

https://github.com/RobertCNelson/stable-kernel

Download Source:

git clone git://github.com/RobertCNelson/stable-kernel.git

Build the kernel:

./build_kernel.sh

Optionally building the *.deb file:

./build_deb.sh


Swapfile

Using a File for Swap Instead of a Partition

On the Beagleboard you should expect to require a swap file given the limitation of how little RAM is available (between 256 MB and 512 MB). Some system programs like apt-get will only run properly when some swap space is present (due to 256 MB not being enough RAM).

Some images (such as those from Linaro.org) do not come with a swap partition or any swap space allocated.

Under Linux, swap space can be either a dedicated partition or a swap file. Both can be mounted as swap which the OS can access.

Creating a Swapfile

The following commands will create a 1 GB file, limit access only to root, format it as swap and then make it available to the OS:

sudo mkdir -p /var/cache/swap/   
sudo dd if=/dev/zero of=/var/cache/swap/swapfile bs=1M count=1024
sudo chmod 0600 /var/cache/swap/swapfile 
sudo mkswap /var/cache/swap/swapfile 
sudo swapon /var/cache/swap/swapfile 

To tell the OS to load this swapfile on each start up, edit the /etc/fstab file to include the following additional line:

/var/cache/swap/swapfile    none    swap    sw    0   0

To verify that the swapfile is accessilble as swap to the OS, run "top" or "htop" at a console.

Ubuntu Software

Wi-Fi Networking (command line)

/etc/network/interfaces

It is relatively easy to configure a Wi-Fi card from the command line.

You will need to edit the /etc/network/interfaces file. There are several guides available via Google.

This is a particularly useful guide http://ubuntuforums.org/showthread.php?t=202834

A sample /etc/network/interfaces file for a WPA2 encrypted access point is:

auto lo
iface lo inet loopback
auto wlan0
iface wlan0 inet dhcp
wpa-driver wext
wpa-ssid <NAME OF AP>
wpa-ap-scan 1
wpa-proto RSN
wpa-pairwise CCMP
wpa-group CCMP
wpa-key-mgmt WPA-PSK
wpa-psk <INSERT KEY XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX>

Your Wi-Fi card will automatically load these settings upon startup and initialize wireless network access.

Lightweight window managers

If you intend to use Ubuntu on the BeagleBoard you can install JWM or IceWM to improve performance.

JWM in particular uses little RAM. On a BeagleBoard with 256 MB, using JWM will leave about 60 MB free in which to run applications.

Web Apps

Midori

Given that the BeagleBoard has fewer resources than a desktop a lightweight browser is more responsive. Midori is a lightweight browser that still supports flash, etc. It is available from the standard repositories: http://en.wikipedia.org/wiki/Midori_%28web_browser%29

Surveillance

Motion

If you have a video source (webcam, IP cam, etc.) which appears as /dev/video0, etc. then you can use the Linux surveillance software "motion" to monitor the video stream and record periods of activity.

Motion is also available from the standard repositories: http://www.debian-administration.org/article/An_Introduction_to_Video_Surveillance_with_%27Motion%27 Using a 960x720 resolution webcam with a 15 fps rate under the UVC driver the Rev C BeagleBoard under Xubuntu reports ~60% CPU utilisation.

To make the BeagleBoard automatically start recording on boot, do the following:

  • Auto Login - run "gdmsetup" from a terminal and select a user to automatically login
  • Sessions - make sure you don't save any previous X Windows sessions so that it doesn't prompt you for which one you want
  • motion.conf - edit /etc/motion/motion.conf to use the settings you want (that is, video output directory, record only video, record in MPEG-4, set frame rate, etc). Do this with "sudo medit /etc/motion/motion.conf" at a prompt.
  • Boot script - create a new script in /etc/rc2.d called "S65motion_client" and set permissions appropriately ("sudo chmod 777 /etc/rc2.d/S65motion_client"). Then edit the file so it contains the following lines:
#! /bin/sh
/usr/bin/motion -c /etc/motion/motion.conf

This will now launch the motion client as root when you boot up.

Also note that unless your BeagleBoard can remember the time (battery backed up clock installed), the timestamps will not be correct until you update the time. If your BeagleBoard has an Internet connection this can be achieved using the ntpdate application.

Robotics

ROS

Willow Garage hosts the open source Robotic Operating System (ROS). While it is natively supported in Ubuntu, the official packages are only for the x86 platform. ROS can be installed from source and is generally easy to do so (although slow).

Following the instructions from here will build and install ROS on your BeagleBoard:

http://www.ros.org/wiki/cturtle/Installation/Ubuntu/SVN

You will need an Internet connection for your BeagleBoard for these scripts to work.

For more information about ROS, see www.ros.org.