Difference between revisions of "EBC Updating the Beagle OS"

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m (Installing a full image on the SD card: Added)
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The '''dd''' takes 5 to 10 minutes.
 
The '''dd''' takes 5 to 10 minutes.
  
Once you have your SD card flashed label it.  All SD cards look the same so it's a good habit to label a card once it's flashed.  Once labeled, put it in the Bone and while holding down the '''S2''' button (the one nearest the SD card slot) and power it up.  The USER LEDs should start flashing. What's happening is the Bone is booting off the SD card and then copying itself to the eMMC.
+
Once you have your SD card flashed label it.  All SD cards look the same so it's a good habit to label a card once it's flashed.  Once labeled, put it in the Bone and while holding down the '''S2''' button (the one nearest the SD card slot) and power it up using an external 5V supply (the USB power may not be enough).  The USER LEDs should start flashing. What's happening is the Bone is booting off the SD card and then copying itself to the eMMC.
  
 
After 10 minutes or so the LEDs will stop flashing and all turn off. Once this happens, power off the Bone, and eject the SD card.  
 
After 10 minutes or so the LEDs will stop flashing and all turn off. Once this happens, power off the Bone, and eject the SD card.  

Revision as of 22:34, 7 August 2014

thumb‎ Embedded Linux Class by Mark A. Yoder

Openlogo-50.png


In this class we run The Debian Distribution on BeagleBone Black. Debian now ships on the eMMC of the Bone. Here's how to tell what version you are running and how to update it.

Finding the version of the running OS

Attach your Bone to your Linux host via the USB cable. Once it's booted, on your host run:

host$ ssh -X 192.168.7.2
Warning: Permanently added '192.168.7.2' (ECDSA) to the list of known hosts.
Last login: Wed Aug  6 11:24:41 2014 from yoder-linux.local
bone$ cat /etc/dogtag
BeagleBoard.org BeagleBone Debian Image 2014-08-05

I'm running the 5-Aug-2014 version Debian. If /etc/dogtag doesn't exist, or is older than shown here, you need to update your image.

Updating your SD image

The Bone can boot from either the built in eMMC (either 2G or 4G depending on which version of BeagleBone Black you have), or from the micro SD card. For this class we'll be booting from the SD card. It's faster to flash, and if you mess up something it's easier and quicker to recover. Booting to newer versions of the OS on the SD card require the eMMC be updated. Yup, that's right, to boot from the SD card you need to update the eMMC. Here's I'll show you how to install a minimal image on the eMMC and then a full image on an SD card.

Installing a minimal image on the eMMC

Plug your SD card into a reader on your Linux host and run Disks.

Unmounting the SD card

Select the SD Drive then unmount any partitions that have mounted. Note at the top of the Disks window is the path to the device. In my case it’s /dev/sdb. We’ll use this path in a moment

Go to http://rcn-ee.net/deb/testing and select the newest date and click on it. You now have the option to select console or lxde. console is the minimal image, so select it. You now have four choices, pick the one that starts with BBB-eMMC-flasher-. It should be a quick download (a minute or so on a quick connection) since it's only 58M or so. Download it. Your file name may look different than mine, but that's OK if it starts with BBB-eMMC-flasher. Next, unzip it with:

host$ unxz BBB-eMMC-flasher-debian-7.6-console-armhf-2014-08-05-2gb.img.xz

This takes about a minute. Then copy it to the SD card. Make sure your of=/dev/sdb matches what you noted above since it may differ from mine.

host$ sudo dd if=BBB-eMMC-flasher-debian-7.6-console-armhf-2014-08-05-2gb.img of=/dev/sdb bs=8M

The dd takes 5 to 10 minutes.

Once you have your SD card flashed label it. All SD cards look the same so it's a good habit to label a card once it's flashed. Once labeled, put it in the Bone and while holding down the S2 button (the one nearest the SD card slot) and power it up using an external 5V supply (the USB power may not be enough). The USER LEDs should start flashing. What's happening is the Bone is booting off the SD card and then copying itself to the eMMC.

After 10 minutes or so the LEDs will stop flashing and all turn off. Once this happens, power off the Bone, and eject the SD card.

You Bone is ready to boot from the new image in the eMMC, but let's not boot from it yet.

Installing a full image on the SD card

We need to repeat the above steps with a different image for the SD card. I suggest you use a different SD card, but the same one can be used.

Return to http://rcn-ee.net/deb/testing and select the newest image. This time when you see console and lxde, select lxde. Here you again have four choices, pick the third, the one beginning with bone-debian-7.6-. Notice it's almost 10 times the size of the minimal image.

Once downloaded, unzip (via unxz) and flash (via dd) like you did before.

Once you have your SD card flashed, put it in the Bone and power it up. This time it will boot off the SD card, but won't copy anything to the eMMC. The USB drive, etc. should appear as before. Connect to it and look around. Does /etc/dogtag show the right version?

bone$ cat /etc/dogtag 
BeagleBoard.org BeagleBone Debian Image 2014-08-05
This prints out how much disk is free.
host$ ssh -X 192.168.7.2
Warning: Permanently added '192.168.7.2' (ECDSA) to the list of known hosts.
Last login: Wed Aug  6 11:24:41 2014 from yoder-linux.local
bone$ df -h
Filesystem      Size  Used Avail Use% Mounted on
rootfs          3.5G  1.9G  1.5G  57% /
udev             10M     0   10M   0% /dev
tmpfs           100M  896K   99M   1% /run
/dev/mmcblk0p2  3.5G  1.9G  1.5G  57% /
tmpfs           249M     0  249M   0% /dev/shm
tmpfs           249M     0  249M   0% /sys/fs/cgroup
tmpfs           100M     0  100M   0% /run/user
tmpfs           5.0M     0  5.0M   0% /run/lock
/dev/mmcblk0p1   96M   72M   25M  75% /boot/uboot
/dev/mmcblk1p2  1.7G  1.3G  322M  81% /media/Angstrom
/dev/mmcblk1p1   70M   54M   16M  78% /media/BEAGLEBONE

The first line is the one we’re interested in. If the Size is much smaller than the size of your SD card, you need to resize your partition. Just enter:

bone$ cd /opt/scripts/tools/
bone$ ./grow_partition.sh
bone$ reboot

This clever script will figure out how big the partition can be and grow it to that size. A reboot is necessary.

Congratulations, you are now running the latest Debian image.




thumb‎ Embedded Linux Class by Mark A. Yoder