Michael, 24 is I2C 25 is SPI 93 is micro wire ..... Andre Abelian -----Original Message----- Do I understand this correctly. Whenever I see Atmel or someone else, I suppose, talking about 2-wire interface, are they referring to I2C? For example, the 24CXX type serial EEPROM's with the 2-wire interface. This is really I2C, isn't it? Michael Brown Instant Net Solutions www.KillerPCs.net "In the land of the blind, he who has one eye is king" -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body