> The data is bidirectional somehow, I forget the details. Maybe
> the keyboard is waiting for something.

Hi Michael

Well that's the puzzle. If you read Section 3 of the keyboard spec
pdf you'll see what's need for the keyboard to become an input
device. I don't believe, or at least see how, my PIC puts it in that
state

a) if the keyboard thinks that is being requested to accept data it
starts clocking. I don't see it doing that

b) isolating the keyboard with the 4066 prevents any signals at all
reaching it

c) sending data from the PIC when the keyboard is idle rules out
a contention condition (plus the 4066 isolation case)

Joe

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