BeagleBoard Black can boot either from internal eMMC (that’s default), or from the external uSD card. The GettingStarted page is useful http://beagleboard.org/Getting%20Started , but it does not give direct instructions for Linux users. And the preparation and booting from an uSD image is very simple.
First, download an image you want to use, for instance from http://beagleboard.org/latest-images
Then you have to decompress it. Ark and tar in the recent version support the .xz format.
Now connect the uSD card you want to use and find out which device it is. I use dmesg for this. Note that normally the card already has partitions, so you’ll have /dev/sdb1 for instance. What we need is the device itself, so /dev/sdb for instance.
The flashing can be done with dd:
dd if=Angstrom-Cloud9-IDE-GNOME-eglibc-ipk-v2012.12-beaglebone-2013.08.21.img of=/dev/sdb bs=64k
Wait a couple of minutes. It takes time.
When it’s done, disconnect your BBB from any power sources and insert the card.
Then press the USER button. It’s the one without clear name, on top of the uSD card, next to HDMI.
Now, keep the button pressed and connect power. Keep it pressed until two LEDs are on
(there will be some blinking during the process).
Then it’s done, you can connect to your BB to verify that you have booted from the bigger image. I’m using minicom or screen:
minicom -D /dev/ttyACM0
or
screen /dev/ttyACM0
