Agilent DSO (80406B or 3202A) acquisition using GPIB

[PAH89]

Hi,

I am trying to acquire raw data from the Agilent DSO 80406B or DSO 3202A and I come across the same problem in each case.

I am using the drivers provided from the instrument driver network; namely "read single waveform" or "read multiple waveforms" for continuous acquistion, the .vi is attached.

The problem is a loss of resolution when acquiring; where the transmitted signal is a simple ramp with even rise and fall times. The imagine in 'acq_signal.jpg' is the acquired signal, which shows the missing samples.

Please could someone provide advice to overcome this problem.

Many thanks,

Paul

[Dennis_Knutson]

It would have been better to save the acquisition in the graph of the VI's front panel and a screen shot of the scope display. Attaching the actual output file would also have been helpful. 

It has not been my experience that the scope does not transfer each and every point that it has captured.

[PAH89]

Hi Dennis,

Please find attached an example of acquired data. In this case the signal looks more like a proper representation of the source, but I don't understand what is causing the line at the point of acquisition? My guess is that it has something to do with the timebase block in the .vi, I just can't get my head around it.

I have also attached the .vi once more, which should have the signal stored on the scope display.

Many thanks,

Paul

[Dennis_Knutson]

The VI has nothing saved. The correct way to do it is to right click on the graph and select Data Operations>Make Current Value Default. Then you must save the VI. It also looks like you are saving the data in your own format. What about just wiring the waveform data type directly to the Export Waveforms instead of using the Get Waveform Components.

[PAH89]

Sorry! I'm sure you can tell I am fairly new to LabVIEW. It should be there now.

I am saving the data in either .dat or .txt because I will use other tools to process and analyse it, I simply want to be able to continuously acquire data from the scope. Wiring the waveform data directly to 'Export Waveforms' has the same effect, I split the waveform into it's components after seeing a tutorial online somewhere.

Many thanks,

Paul

edit: attached wrong driver --- correct driver now attached.

[Dennis_Knutson]

Here is a file created by the standard Export Waveform function with a waveform as an input and a quick and dirty VI that reads it. Your text file has blank lines and other issues that you are probably not importing correctly.

[PAH89]

So to be clear; if I save my waveform using that sequence it should be ok? I can't test it at the moment since I am out of my office/lab until tomorrow.

I can save a single waveform measurement without any error, it's the introduction of the while loop that causes the problem I believe, when the loop goes back to the start it must start recording the data from whatever point the signal is at instantaneously rather than continuing from point at the end of the while loop iteration, if you see what I mean!

I appreciate your help.

Many thanks,
Paul