One other difference: RA4 does not have a protection diode to Vcc. This can be a problem or a help: It is a problem if you have a nasty spike come in the port. It is a help if you have a signal on that port that normally goes above Vcc (up to a chip-specific voltage -- see the data sheet). 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