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Taking ONE Voltage Value at High Frequencies

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Taking ONE Voltage Value at High Frequencies

Hi all!

 

I am using the USB-6215 to prove the Compton effect. I have a trigger pulse going into my counter PFI0 and a variable height square wave approximately 3 micro seconds incoming after the trigger. I then want to collect all read voltage values and send them to a histogram. I am missing BOAT LOADS of counts when taking N-Samples (2 samples) at 250k Hz. Is there any other way to increase the number of times my device is triggered so that I can take more samples? I notice that at a lower sampling rate for this configuration I end up completely missing the variable voltage pulse. Is this hardware just not equipped to deal with this frequent of signals? If so what device would you recommend?

 

I have attached my code below.

 

Thank You!!!

 

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Re: Taking ONE Voltage Value at High Frequencies

How fast do you need to sample? That particular hardware should be fast enough, but looking at your VI, you are creating a new task each loop using DAQ Assistant, which is very slow. Also, trying to get your elapsed time by placing the Elapsed Time Express VI inside your while loop (which again the express VI's are really slow), you are actually making your loop take longer to run. If you want to know how quickly your loop is running, look into benchmarking your code. (See the link below)

 

Benchmarking a portion of LabVIEW code

http://www.ni.com/example/25532/en/

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