[beagleboard] First steps with the BeagleBone PRU

Great write-up and demo!

I'm not familiar with DMX, but I would like to point you to RPMsg and
virtio [1]. From what I understand from the Linux hackers around me,
it would likely be the best architecture for communicating between the
processors and the driver should be rewritten to use it. Don't want to
slow you down, but if you are still looking at the architecture of the
communication, consider it.

[1] http://omappedia.org/wiki/Category:RPMsg

Second, it would be interesting to create a firmware image that
allowed you to do Arduino-like things. [2] is what I've seen.

[2] https://github.com/ecto/duino/