I am porting eLua to the Atmel SAM3/4 processors, in particular the SAM3X8E used in the Arduino Due.
Port is running, with support for the serial console and several devices.
PIO - works
UART - works, except for buffering (xmodem does not work on serial console). Hardware flow control written, but not tested.
USB CDC - works, except for buffering (although attached build does not use it).
Timers - works
PWM - works, but has some issues (sometimes the drivers return wrong values to eLua, but it does work). Have not tested for accuracy of frequency or duty cycle. So far just uses the