> I want to be able to select, this is where the PIC
> comes in. I want the PIC to listen and if it sees a
> special key sequence it will turn off one of the tx/rx
> AND gates and turn on the other tx/rx AND gates.
> Allowing communication to the other computer.

A possible problem is the signal voltage. If your PCs
are using +/- 12V levels (ie not 5V) then you won't be
able to pass the comms through a standard gate. If
you can get a +/- power supply from the MAX chips it's
possible you could use 4066's or 4052's to select and
route the signals

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