Finite Number of Data Points using DIO-32

[billaf]

I have a system designed to scan a field of view and acquire data at each point in the field of view. The acquisition process does not begin until the system/clock is initiated. It is not continuously clocked and cannot be. I am trying to run this process at 25kHz using all four data ports of the DIO-32 board. At this rate, the VI seems to miss clock triggers and does not acquire the proper number of points. Currently, I can only run the process at 6kHz. I know the board can handle a faster data rate than this. Can someone please suggest a fix or provide an example VI that can do this. Will it help me to make my VI an executable using App builder (which I don't currently own)?

Thanks,
Bill

[Geneva L.]

Bill,

Are you referring to the PCI-DIO-32HS? This board is in the 653x family of digital boards. It sounds like you are either trying to do pattern input with an external clock, or burst mode handshaking input with an external clock. You should check the 653x User Manual to determine which method is actually better for your application. You can view the certain conditions for which data will be latched in. There are also benchmarks on transfer rates in the appendix of the manual that you can view for comparison. Examples get installed with NI-DAQ and are available in the LabVIEW >> Daq >> Digital >> 653x.llb directory. There is an example for each of the types of operations I mentioned above. I recommend testing with a function generator first, so that you c
an focus and isolate the issue with just the PCI-DIO-32HS board before moving on to your program and/or using your external devices with the board.

Regards,
Geneva L.
Applications Engineer
National Instruments
http://www.ni.com/ask