I have a project that needs a small display and input and I also have an AVR butterfly lying around.http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3146 I would need to be able to reprogram the butterfly and talk back and forth with it over serial.
I don't want to wander aound in a swamp though so I wonder if anyone has done this. The butterfly expects to be programmed over RS232 serial which I don't have and it runs at 3V. I was thinking of using ICSP to program it but my pololu usb programmer won't work down that low.
I assume that, if i can program it, I can load soft serial in it so i just ignore its rs232 pins. I don't think level shifting from the arduino to 3.3 would be too bad, probably only needed on the butterfly's input.
so, just throwing this out there looking for hints while I look at my avr dragon doc and see if it will program a 3v target.