> Yes that's SO close. it is missing however the input
> PC.
>
> 1 pc to connect to 2 different PC's

OK, now we're getting down to it. Both of these answers
have the gates/232 direction flipped, as it's now 1 into 2,
not 2 into 1

Does the source PC decide which other PC it talks to
or does the PIC decide ?

If the source PC decides, possible solution - keep the
circuit pretty much as it is and use one of the handshake
lines of the source PC to do the switching

If the PIC decides then you can use a slight re-arrangement
of the circuit I sent. Substitute the source PC for the PIC, use
the PIC to monitor Tx from the source PC and enable the
appropriate pair gates

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