>The peripheral I'm communicating with is documented as using : > > "Data length 8 bit > Stop bit 1 bit > Parity even > Baudrate 4800 bps" It is a bit unusual to use both parity and 8 data bits, but certainly not unheard of. I am guessing that you should try it both ways. Can you do some quick testing using HyperTerminal to find out which it is, and eliminate any possibility that it is your hardware. Bob Ammerman RAm Systems -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads