You're not related in any way to a person called T. Pratched[1]
Not that I am aware of...
If you were, you could use the Semaphore network ;-)
Hmmm.. Assuming Semaphore means what I think it does in this context, it
would e fairly easy to make a semaphore transmitter that is driven by an
RS232 port, the receiver is a lot more work. And what aobut the data
rate? If you need to keep up with 1200 baud, that's about 120cps, those
arms are going to be flying about, unless you have some kind of data
buffering at the transmitter end (which brings us back to another solution).
Not to mention, of course, that this is strictly line-of-sight, something
that's not possible here.
-tony