I am a new user to Labview with about three weeks of experience using Labview 8.2. For the most part I have been able to set up some vi without a lot of issues. One problem that I am having that I cannot get a grip on is the data stream that I get from a DAQ call. I set up the DAQ to a continuous mode with the sample size at 1 and the sample rate at 10 Hz. I then enclose my vi with a timed loop that is set anywhere from 20 seconds up to 60 seconds. The data is then sent to a file for analysis. The problem is that instead of getting what I think should be 1 reading per time base (1 second or 60 seconds), I get multiple readings of the same value. The test I am running is physically changing values every 10 to 15 seconds. I changed the DAQ to an actual sample number without being in continuous mode and my data then seems to be right. The only problem with that setup is the DAQ will not allow me to go to just one sample. This makes me have to filter my final file. I do not understand what I am actually getting when you trigger or query the DAQ for a reading? Is there a buffer there? If so how do handle it?
