Hello all.

I am trying to implement a 2-wire serial communication link between
multiple PICs.  I will have one master, with several remote slaves.  The
slaves will each have a keypad, an LCD display, and an auxiliary output -
only 2 lines remain, one for the serial clock and serial data.

I have been having difficulty developing a protocol for the communication -
should the slaves poll the clock line or they be interrupted?  If
interrupted, should they ACK before the master sends data?

I would appreciate any help/guidance on this matter.

Regards,

--John