Splitting RS-232 Signal?

Splitting RS-232 Signal?#8890

By LaserGecko - Sat Dec 31, 2005 4:32 pm

- Sat Dec 31, 2005 4:32 pm #8890

Hi there,

I'm getting ready to have a PCB made through the BatchPCB website, but I have one final question that I can't seem to answer.

How can you split an RS-232 data signal so that two devices can read it? I would like for my GPS interface board to be able to send to two devices. It's a one way stream since neither of them would have to send anything back to it.

Do I need to use one of the MAX232 chips or can it be something simpler?

Thanks!
Jason

#8891

By wiml - Sat Dec 31, 2005 4:57 pm

- Sat Dec 31, 2005 4:57 pm #8891

You could just connect the Tx pin of the transmitter to the Rx pins of both of the receivers. The receiver puts some load on the line, so you can't attach an arbitrary number of them to a single transmitter, but two ought to be OK.

If there's flow control or anything like that involved, then it gets complicated, but usually there isn't.

#8893

By LaserGecko - Sat Dec 31, 2005 6:41 pm

- Sat Dec 31, 2005 6:41 pm #8893

Thanks for the reply and info.

There's no flow control or anything, so that's not a problem. I'm making an interface board for a GPS module and want to be able to drive the encoder board and an external serial port for use with an optional laptop. Right now, I just have an extra jumper pad on the trace so there's an easy place to attach the DB-9 connector.

Looks like I may be ordering the prototype sooner than I thought!

Thanks again.

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