>
> incoming signal - buffer -=- resistor - buffer -=- outgoing signal
>
> the PIC connects to the = places. it can receive the signal, or block it
> or not, or even send something of its own choice to the next PIC (I did
> not use that). after power up there was an 'address resolution phase'
> where every PIC got its address, first one first, after it received its
> address it unblocked comm to the next and kept its assigned address.
>

Not completely clear to me - what happens if one of the controllers in
the middle of the chain dies/hangs/etc?
Actually I'm thinking about the same application - greenhouse
controller network, just not for commercial application.

-- 
KPL
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