Would like to measure the amplitude of a signal as attached file 'Ori.jpg', if using N samples method (1k samples, 239kHz rate) for data acqusition, the result was perfect as file '1k_N.jpg'. But the speed was too slow. Though the continuously sampling method carried out much faster, the values were not usable. As files '1k_continuous.jpg' . Do not know what cause these outliers, and it not occured occasionally. The 10.5537 should be the maxmum reading value of NI 6361. Btw, is that impossible to accelerate the N sample method? Even tried 20 samples instead of 1000, the loop still cost similar time. The DAQ was not stopped in each loop. Helps with either decreasing N sampling time or taking correct readings from continuously sampling method are greatly appreciated. Pem

In the N-samples version the DAQ Assistant only acquires 200 samples each time it is called and it returns oll of them. In the continuous sample version samples are acquired at 59000 per second, whether they are read or returned to the main program or not. So at a loop rate of 20 ms per iteration about 900 more samples are acquired than read on each iteration. When an error occurs the DAQ Assistant stops the task and Unreserves it. The next time the loop iterates the DAQ device will be reconfigured. I have no way to know for sure, but it is possible that some spurious values get into the buffer during the stop/reconfigure process. Lynn

LabVIEW

Continuous sampling method get unreasonable values

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Thanks Lynn,

The stop/reconfigure process may result some noise. Appreciate for your answer and patience

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LabVIEW

Continuous sampling method get unreasonable values

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