PAUL James wrote:
> It seems to me that with the talk so far about this, it appears as
> though this is a peer to peer system.
> So when one unit talks, the other one listens.  And if it is listening,
> it knows enough not to talk at 
> The same time.  Or at least I would think so anyway.

I agree.

> If it master to slaves, then there must be a way of addressing which
> device you want to talk to.  If this
> Is the case, then when each slave notices that there is a bit on the
> line, it would participate in the handshake
> By pulling the other line low momentarily, then releasing the line.

Ooh... We've been talking about a single slave so far.  Multiple slaves 
is much more complex.

Essentially, you need to confirm that EVERY slave has received the bit 
before you're done sending it.  And they might try to acknowledge it all 
at the same time.

I suppose you could figure out A/D values for LZZZZ vs. LLZZZ vs. LLLZZ 
etc. (using Scott's notation with four slaves for example), and consider 
it fully acknowledged when you get to LLLLL (but not LLLLZ), but that's 
splitting it quite fine.
-- 
Timothy J. Weber
http://timothyweber.org
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