I have connected CDAQ9189 using ethernet to my computer.
I am using 9205 card to acquire a sine wave of freq 1Hz, amplitude 1Vpp.
I am using nidaqmx with python to save the data. However, the behaviour I describe below is the same when seen using test panel in NI-MAX.
Periodically, the output from the card goes to zero repeatedly after giving the expected reading for a few data points.
I have tried changing the number of samples per channel, the sample mode (FINITE and CONTINOUS) and the number of samples to acquire. The number of zeros and actual data points depends only on sample rate.
At 500 Hz sampling 4 zero values and 6 data values of sine wave are acquired.
At 2000 Hz sampling 16 zero values and 24 data values of sine wave are acquired.
At 5000 Hz sampling 40 zero values and 60 data values of sine wave are acquired.
I have attached the pictures of the sine wave, zoomed picture of the same wave and the python code I am using to acquire data.