Instrument Control (GPIB, Serial, VISA, IVI)

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Serial-port COM2 always suddenly answers! Why?

Hello Everybody.

I have an embedded controller PXI-8186. In order to test the functionality of the COM-Ports I connect an other PC with a running terminal-software to look what happens on the serial ports. I built a serial communication-VI to be able to receive and write data to the serial Ports. I used the VISA-serial VI´s.
COM1 always receive and send the correct bytes with this VI. But when I send something to COM2, it always suddenly send a string "<0>"!

Do anybody know the reason???

Thanx

Norman
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Hello Ben

Have you the same problem if you receive and write from port 1 to port 2 or from port 2 to port 2 without your other PC (connecting Pin 2 and 3)?
Have you set the correct bound rate?


regards

Manuel
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Hello Manuel

Yes, I´ve tested it befor with a communication between COM1 and COM2 in both directions. But everytime I´ve got a timeout on the receiving Port, so I use the terminal programm on my laptop to look what´s happened on the serial Ports.
Furthertmore, if I send something out of my COM2 Port of the PXI, it always add 00 at the end of the string i´ve sent.


Do you have any idea?

Best regards
Norman
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Hi Ben,

are the windows (do you use windows?!) settings of your com ports exactly the same?
you find them in your hardware manager under com ports. you can set things like flow control, baud rate, ...

greets!
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Hi Watermann,

I use Windows XP and I have checked the COM Port settings and they are absolutly the same for both Ports, except the IRQ and memory adress of course.

This is not the problem.
Nevertheless thank you for the answer.

Norman
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