At 07:02 PM 1/24/02 +1300, you wrote:
>
>So has anyone bright ideas for 2-way 2-wire comms using the
>Vcc line ?

I've used 1-way 2-wire comms on 3 or 4 different products in the distant
past.  Correct me if I'm wrong but won't this work fine for half-duplex?
Each end of the link has to be in on the joke, of course. If not using a
polled method, then for async operation, you must do something to handle
collisions.  My first approach would probably be along the lines of
master/slave: don't talk until you get permission. Of course then, the
master must poll often enough to deal with all matters at hand.

>I think there are still laughs to come with this job.

That's why we are all in this vocation, isn't it? :)

>Yet to find out
>what type of clocks they have that can go backwards when they
>adjust for local time

Of course, you could take the other approach and pump then around forward
11 hours (or 23 hours if dealing with 24 hour clocks).

Good luck!
Tom M.

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