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Hey Guys, Been using the PXI-6509 card now for a while, but came across a situation i'd never seen before. Just thought someone could either confirm or elaborate on what it is i'm seeing. With all DAQmx read tasks you can setup Sampling Rate and the # of samples to read. So for example, rate = 10kHz, samples=10k, it should take 1 second to read the 10k samples. I dont see a problem with this. But when you get the read VI to output a waveform (Digital->Single Channel -> Multiple Samples -> Waveform), there does not appear to be any dt parameter. I.e the time between sampling points. See below. Now from what i can tell it seems that the sampling frequency (for the 6509 card) set in MAX is ignored and the card just samples at its maximum rate which appears to be around 1MHz. If i then set the dt value of the output waveform to 1uS, i can then extract the correct frequency information. The 1uS does not seem to be exact it appears to be approximate. Even when the task set up in MAX is set to a rate of 1Hz and read 10 samples. The VI does not take 10s to complete, it finishes quite fast. So my question is... Does the PXI-6509 card ignore the sampling rate set up in MAX and just use the maximum sampling rate of 1MHz?? Thanks for any help, it appears it does just would like someone to confirm or explain it if i'm wrong.