Instrument Control (GPIB, Serial, VISA, IVI)

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How do I communicate with ComputerBoards 7044 DI/O serial module

I can send commands using the software provided with my serial module and my DI/O's work fine. But when using labVIEW's basic serial read write VI, I get no response. When I perform a loopback test it works fine. I have also created an additional VISA read/write with the same problem. Any Ideas?
Example code is of form #011201 (write to channel 2 on board 1 a value of logic high). Do I need to include any other characters when using labVIEW? Thanks
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Can you communicate with it using Hyperterminal? Are you adding a termination character to the end of the command? This should be something like a CR or LF. Be sure you are using the actual control code. The easiest way to be sure of this is to use the constants on the string palette.
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Hi,

I don't know if the instrument that you have is a Hameg 7044. If it is you can try downloading the driver from the following link.
Hameg 7044

Usually when you cannot communicate with an instrument is because you are missing some special characters or termination characters. This is very common when getting a timeout error. You can check on the manual of the instrument and it should say what termination character to use.
As Dennis suggested, you can try communicating with it through Hyperterminal. It would be a good idea to also start capturing the communication in NI-SPY to see if you are missing some characters or som
ething. You can find NI-SPY in Windows»Start»Programs»National Instruments.
I hope this helps.

Best Regards,
Ricardo Santa Olalla
National Instruments.
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Thanks Dennis....Beginner Mistake....I didn't have a termination character at the end of my command. The Advanced Read Write .VI in labVIEW worked. Thanks for your help, JD
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