>just to check if any one have any experience in using the >MAX 232 chip with a voltage source of 3.3 instead of 5 Volt Not sure if the MAX232 is rated for 3V, I suspect it is only 5V Use the MAX3232E instead. IIRC pin compatible, and definitely allowed to run at 3V. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads