I am reading data from a PCI-6220 DAQ card (4 channels). When I use the Write LVM VI, the data is recorded with an X-Value staring at 0 incrementing at the expected sample rate. The Time-Pref is Relative. A single header was configured and it displays the correct date, time, channels, etc.
However, when I pass the same data through the Signal Compression VI with a reduction of 10 and the mean selected and plotted, a number of differences are seen. The header is missing and the X_Values start at 3.20E+09. The Time_Pref is Absolute with a date of 12/31/1903 and time of 17:00:00. Also, if I stop acquiring data the raw data shows the correct time gaps in the data (plotting on a chart) once I resume. However, the Signal Compressed data erases old data and restarts. When I use a probe to look at the data going in and out of the Signal Compression VI, it looks the same.
Any ideas?
Thanks, Mike