BeagleBone LEDs with Arago Kernel v3.2
If you boot your BeagleBone using the supplied micro SD card image, there are two LEDs (near the Ethernet jack) that will blink. D2 (USR0 on the schematic) will blink a heart beat, and D3 (USR1 on the schematic) will blink on SD card access.
This is really handy. Since the Linux kernel is actually performing the blink operations, as long as the heart beat is going, the kernel is running. And if your BeagleBone is not responding well, but the SD card access LED is flashing like there’s no tomorrow, it’s just because SD cards are slow and a lot of disk access is going on.
I’m running Debian 6 Squeeze armel on my BeagleBone. I now have blinkin’ lights!