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Instrument Control (GPIB, Serial, VISA, IVI)

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VISA read seems to be getting transmit buffer?

I'm communicating with a Keithley 2010 Multimeter using Labview 7. I'm using VISA read/write commands
and have two different programs. One seems to work.
The other seems to return the contents of the transmit
buffer rather than recieve buffer. The two programs handle communication using the same vis and are almost identical (hard to really describe the difference without using a lot of words). Anything I'm missing? I've tried a lot of differnt properity node variations, but none seem to work.
Any help would be most appreciated.
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Get NI Spy captures of both programs to see how they are operating differently, and what is being returned. If you are using RS-485, it is possible that you set the DTR with echo for the tranceiver mode in the program that is giving you the contents of the transmit buffer.

NI Spy Tutorial


These two example programs may be of use to you when analyzing your spy captures.
Compare the Differences Between Two NI Spy Captures *requires MS Visual Studio* *Note: Use a simple compare*
Convert an NI Spy Capture into a Spreadsheet File *helpful for reformatting spy capture for easier printing*
http://zone.ni.com/devzone/devzone.nsf/we
bcategories/BFEA3A69F40A9F8C862569FD006FFCF6?opendocument&node=DZ59203_US
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