I have a PC with 3 com ports, 1, 2, and 3. I have a PC controlled device that has transmit and receicve indicators. When connected to com 1 or com 3 the device works properly. When connected to com 2 the transmit indicator stays on. I checked the voltage on the pin and I am getting +11.05 VDC on pin 3 of com port 2, on com 1 and 3 I get -11.05 VDC. This is true on all PCS of this particular model approx 60 PCs. Is this normal ? If so why is this normal?
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Serial Port Help.
- Thread starter jeff1
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Pin 3 floats as it is a receive data pin. And it may be affected by the RTS/CTS on the respective port.
All 25 pin connectors? With pin 7 as common you should have -9 to -15 on transmit and float on receiver on the PC. Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.
All 25 pin connectors? With pin 7 as common you should have -9 to -15 on transmit and float on receiver on the PC. Ed Fair
unixstuff@juno.com
Any advice I give is my best judgement based on my interpretation of the facts you supply. Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.
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