>I wonder if i2c has no lower speed limit. This would >allow anyone with a voltmeter to troubleshoot it. Well I am running it at 10KHz as I have opto-isolators in the circuit. Don't have any problems at that speed, and there are eeprom chips on the line as well as slave PICs. -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads