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Does anyone know how I can split a serial cable so the output from one device is connected as inputs to two different computers?

I try to connect the (-)(+)TX at the same to the two computer... I get data but wrong data with "? , % " some wrong chars

Please can someone help me with this.


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Did you make sure to connect them with a null-modem/crossover cable? – Synetech Jul 19 '12 at 18:35
"... connect the (-)(+)TX ..." - Differential signal?! What kind of "serial" is this, RS-422? Typical serial connections are intended to be point-to-point unless explicitly designed as multipoint. The line driver (the IC, not the SW) may not be able to cope with a split; long cables and/or small gauge conductor make it worse. Are you positive that this is a one-way connection, i.e. there is no handshaking involved? – sawdust Jul 19 '12 at 19:27

Maybe have a hunt around electronics shops because this used to be a common requirement.

I think I've got a splitter in my "box" of old bits of kit.

It is much better to have a proper box because of the possibility of bleed over of the signals.

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enter image description here


You can of course buy RS232 splitters rather than make your own.

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