On Tue, Dec 18, 2012 at 10:40 AM, Caleb Phillips <cphillips@areai.aero> wrote:
We built a board that has a MAX3013 chip for level converting. Also a MAX3387E for RS232 comms.

I think even a level converter like this one should work:
https://www.adafruit.com/products/395

For what it's worth, I've used the 8 channel adafruit level translator (linked above) and have had success with serial communication, spi communication, and pwm signals for servos.

Regards,

Curt. 
--
Curtis Olson:
http://www.atiak.com - http://aem.umn.edu/~uav/
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