Hello, someone knows if the PIC16F873 have some problem with using I2C @ 400kHz? Or maybe CCS have a problem with it's built-in I2C functions? I'm using the hardware I2C: #use i2c(master, sda=PIN_C4, scl=PIN_C3, FORCE_HW, FAST) It's very strange, because at 100kHz (SLOW) everything works fine. I have 1K pull-up resistors and the circuit is on a PCB. The PIC and the 24C64 is distant only 3 inches, so PCB traces capacitance wouldn't be an issue. Best regards, Brusque ----------------------------------- Edson Brusque Research and Development C.I.Tronics Lighting Designers Ltda Blumenau - SC - Brazil www.citronics.com.br Say NO to HTML mail ----------------------------------- -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body