tektronix

[labviewproblems]

I am having a problem with changing the settings on my tds 2024b while I am acquiring my signal. When I put the settings in the while loop to change them while I am aquiring my signal it does not aquire the whole signal only a really tiny piece. I need to be able to operate the labview code like I am operating the oscilliscope but only on the computer. Someone pls help

[Dennis_Knutson]

You can't do that programmatically. You must wait for the data to be completely transferred. Otherwise, the instrument will report a 'query interrupted' error. I can't look at your VI since I am posting by phone.

[crossrulz]

You need to allow the oscilloscope time in order for it to capture the signal.  Therefore, you should probably add a wait after setting it to run mode to allow for the trigger and the waveform to be fully captured before asking for the waveform.

[labviewproblems]

I tried the wait vi for the program but for some reason it didn't work, I put it inside the while loop

[Dennis_Knutson]

What sort of wait? Are you now waiting for the data transfer to be complete before changing the settings?

[billko]

I can't see your code because I don't have the latest LabVIEW, but from the quetion and responses, I gather you are using the Tektronix flavor of SCPI.  I believe Tektronix supports the *OPC? query so you can use that instead of a hardocoded wait.

[labviewproblems]

just the wait until next multiple, that way if I get to end of the scope processing time it will work for the next multiple so I can aquire all the signal in any given time frame. I was thinking of putting a timed loop of sorts for my changes with the oscilliscope

[Dennis_Knutson]

None of that seems like a reasonable solution. It's the acquisition times are fast, a cheap way is to put the acquisition in a timeout event of an event structure and the controls in their own events. A notifier in the acquisition loop would tell the loop with the controls that it can write. In any case, you have to do things sequentially since that is how the instrument and GPIB is designed.

[labviewproblems]

the configure channel vi comes before the actual signal, how would I give the signal enough time to aquire then be able to change the settings afterwards?

[Dennis_Knutson]

Besides the two approaches I already said, you could use a state machine.