Arduino Due experimenting

[teachop]

It works on Arduino Due with only slight adjustments. Nice.

Not much on the .rb side was needed at all. On the host side it experienced a few communication synchronization / timing issues. What made it robust was adding a common read routine with retry after a usleep timeout mechanism. Also O_NONBLOCK is set for the serial port open. Perhaps USB serial port timing is a bit different on the Due.

I think your gem is a great idea, very helpful. Good work!

[kyab]

@teachop Thanks again for your trying! Maybe I can merge if you pull-request your adjustment.

[teachop]

Yes I will clean the Arduino Due adjustment up for a pull-request.