>     have you managed to use fast IIC (400kHz) on a PIC16F877?

Yes.

>     I'm trying to do it with a 'F877 and a 24C64, no sucess... :(

The PIC MSSP in IIC master mode has a bug where the ACK bit is sampled on
the wrong edge of clock, causing a race condition.  You may be running into
this.  A small cap on SDA will work around this problem but also limit your
max bit rate.  I consider 400KHz the upper limit with the MSSP in master
mode because of this.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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