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DAQ collecting finite samples despite being set to continuous acquisition mode



I've created a vi which reads data from one channel on my USB 6225 OEM device, displays the data to a chart, and writes the data to a .csv file using the write to spreadsheet file vi. The DAQ acquisition mode is set to Continuous Samples; however it behaves as if it were set to N Samples, as the number of data points written to my .csv file is equal to the number specified in the Samples to Read input.


I replaced the DAQmx Assistant vi with the Simulate Signal vi and observed the same behavior. Why does this happen?


Attached below is my vi.

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Message 1 of 4
When you specify number of samples to read, you are supposed to get that number of samples. Anything else would not make sense. Continuous means you have no gaps in the acquisition. Don't confuse it with finite mode.
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Message 2 of 4

When the acquisition mode is set to continuous samples, the samples to read input becomes the buffer size -- not the number of samples read. I expect the DAQ to collect samples until I stop the vi. This is the behavior I have always seen in the past, so don't know why it is any different this time. 

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Message 3 of 4
Continuous mode will collect all requested samples until you stop the VI. For example, 1000 Samples/sec with 100 samples will return those 100 samples with each DAQmx Read and this behavior has always been there.
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Message 4 of 4