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Labview fast acquistion with trigger

Hello,
I am using a DPO 4104 oscilloscope to take waveforms.

I trigger them by a certain value and my VI can save them to a table.

 

This VI I built works really good but it's way to slow. The fastest rate I got was about 3 Hz and I need about 100 Hz.

 

If I get Waveforms from the oscilloscope with 1000 points the files are about 26kb large.

By a 100 Hz rate I'd get 2,6Mbyte per sec which should be okay as I am having my scope connected via usb.

So it can't be a bottleneck in the usb connection I guess.

However it's still too slow.

 

Can you guys please check whats wrong?

 

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Message 1 of 4
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1. You only need to setup the trigger once.  So move that to before the loop.  That will eliminate a 200ms wait that is in the driver.

2. You are getting the timestamp from the scope.  Why make your own?

 

Even with that, I would not expect you to get more than 10 waveforms/second due to a 100ms wait in the waveform capture routine.  To get the rates you want, I think you will need to go with a DAQ board, preferably PCI(e).


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Okay thanks, I put the trigger in front of the whileloop.

However the rate is only minimal faster.

Why is there a 100ms wait in the waveform capture routine?

I've tried to connect via ethernet but rates were even slower for some reason.

 

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Also where can I buy this DAQ card? And how will it speed up my acquisition with the bottleneck in the measurement vi?
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