Re: Splitting serial cables ?

In article <43DD3DBC.6E32BF1E@xxxxxxxxxxxx>, JF Mezei <jfmezei.spamnot@xxxxxxxxxxxx> writes:
> "Steven M. Schweda" wrote:
>> First figure out what is supposed to happen to all the outputs you've
>> wired together, and who wins the arguments when one says "+12V" and
>> another says "-12V".
>
> Since an OPA0: doesn't have modem controls, is that still a big problem
> ?

Transmit data is on one of those wires. You have two stations both
wired into transmit data. Both of them will be holding that lead
in the space condition (or mark -- I can never remember) when idle.
This is not tri-state logic where the lead floats when idle.

If you've ever put a breakout box on an RS232 connector, you'll have
noticed that TD and RD are always live.

> The goal isn't to have multiple people writing to OPA0: at the same
> time. That would indeed cause gibberish.
> The goal is more to log the output opf OPA0: to two different ports and
> possibly have one of those ports send data out at a time.

You can have one source sending data to multiple receivers. That's
no problem since the receivers aren't trying to coerce the signal line.

You can't have multiple sources sending data to a single receiver.
That's a problem since multiple senders are each trying to coerce
the signal line differently.

.