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How I must progrmar ni-scope to make a continuous aqusição of data?

I am with problem to obtain the acquisition of data and to save the data to exactly tempo.O time desired for the acquisition is between 3 and 10 min.Como I must proceed?
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Message 1 of 6
Because you're using NI-Scope, I'm assuming that you'll be sampling at a fairly fast rate.  Thus, you will be saving fairly large chunks of data to file.  Fortunately, there is a LabVIEW shipping example that is designed to stream data to file.  In LabVIEW, go to HELP >> Find Examples to launch the LabVIEW example finder.  Then browse to: Hardware Input and Output >> Modular Instruments >> NI-SCOPE >> Continuous Aquisition.  Within that folder you will find an example called: "niScope EX Save to File - HWS Low Level - Single Channel Stream.vi."  This VI is designed to stream large amounts of data into a HWS (Hierachical Waveform Storage) file.  If you look at the code, a produce/consumer loop architecture is used to make sure that data is not lost but preserved in PC memory in a queue. 
I would try running this example to start with.  When I ran the example on my computer, I changed the MAX Queue size in the block diagram to be 1000.  Because your digitizer can sample data faster than your PC can write it to file, it is important to use a large queue size to store data in memory.  That way, the produce loop (which acquires from the scope), can continuously acquire data.  The consumer loop (file writing loop), will run continuously until all samples have been written to file, even if this takes longer than your aquisition time.  Hope this helps!
David Hall | Applications Engineering | National Instruments
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Message 2 of 6
Thanks for help!I obtained to make the acquisition with susesso, but now I desire to locate the data in graph, as to proceed?
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To see the data in the graph, you will need to add a graph or chart indicator on the front panel.  Note that this example reads the data back as an I8, which still must be scaled to be useful data.  Try opening the example "niSCOPE EX Stream to Disk."  As you can see in this example, the array of I8 data is scaled and then plotted on a graph.  This example might actually work for you in the long run...depending on how fast you are sampling.  In general, you can stream to disk at about 10 MB/s.  The "niSCOPE EX Stream to Disk" example will probably work for 3-10 minutes as long as you are sampling fairly slowly.  Hope this helps!
David Hall | Applications Engineering | National Instruments
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I have a problem whith example "niSCOPE EX Stream to Disk.This occurring error with the vertical  configure.
  I would like to know as to locate given of an archive save for example the example "niScope EX save to file - HWS low level -single chanel Stream.vi"
Thanks for help!
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Message 5 of 6


It might be helpful to know what specific error occured at the configure vertical VI.  Common errors include setting an incorrect input range or gain setting.  If you gave the error code or description, it might be possible to explain why that error is occuring.  Hope this helps!


David Hall | Applications Engineering | National Instruments 

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