I am trying to save a waveform that was recorded by a DAQmx device into a .wav file. I have found two sample vi's that I used to start with. Sound Input to File.vi This vi saves the waveforms from a microphone input to a .wav file. The nice thing about this vi is it has no limit on how long you can record. SVXMPL_WAV Record (DAQmx).vi The vi saves the waveforms from the DAQmx input to a .wav file. The nice thing about this vi is it shows how to get the waveform through the DAQmx device, but you can only record for just over 1 minute. DAQmx Input to File.vi This was my attempt at combining the best things of the above vi's, but it doesn't work and I don't know why. I'm hoping somebody can tell me where I went wrong and/or how to improve my vi. Thanks Number 6

Hi Prisoner, When you try to acquire more than a few minutes of data are you getting an error message that states the requested memory could not be allocated? This error appears because the program tries to all acquire data in a single DAQmx read call (1 channel N sample). You will need to instead, modify the program such that you call DAQmx read multiple times so you can use a smaller buffer size. The best way to change this would be to implement a producer/consumer loop where the producer queues all the samples and the consumer dequeues them and feeds them to the Sound Write Waveform VI. Application Design Patterns: Producer/Consumer http://zone.ni.com/devzone/cda/tut/p/id/3023 Producer/Consumer pattern https://decibel.ni.com/content/docs/DOC-8962

Dynamic Signal Acquisition

Continuous Saving from DAQmx to a WAV File

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Thanks for sharing!

Anthony F.
Staff Software Engineer
National Instruments

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Dynamic Signal Acquisition

Continuous Saving from DAQmx to a WAV File

Re: Continuous Saving from DAQmx to a WAV File