>I have been trying to implement a basic I2C demonstration
>between 2 PIC 16F877s using CCS PIC C.  One PIC is the
>master and the other the slave.  Unfortunately I am a bit
>unclear about the wiring and the code.
>  So, if anyone out there has the inclination, I have a
>couple of questions:
>
>First, do I need to have a common ground between the PICs?

Yes, just like RS232 and any other device. The only ones where this may not
be necessary are transformer coupled differential or balanced signals.

>I have tried the following master and slave code with several
>different wiring configurations but none seems to work, any ideas?

Get copies of AN734 and AN735 off the Microchip website, and do your C
coding just like their assembly coding. The only gotcha in this code is
listed in this message in the archive
http://www.piclist.com/techref/postbot.asp?by=time&id=piclist/2002/03/24/172
354a&tgt=_top&key=877+I2C+slave+%2D+does+it+work+using+the+MSSP&from= which
produces a very long URL that is bound to wrap. as an alternative look for

piclist 2002\03\24\172354a

Thread: 877 I2C slave - does it work using the MSSP ?

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