Hi,
I'm currently working on a automatic testing sequence with the help of a cDAQ 9178 containing amongst other things an NI 9269. I have written a LabVIEW .VI for writing data to this module and there I can without any problem run it at the modules maximum speed of 100kS/s. When I'm implementing this in TestStand my plan is to use a StationGlobal variable to control the amplitude of the written waveform. All this seem to work as it shold but when I'm starting the VI to begin writing data to the NI 9269 I can't get anywhere near it's maximum speed, I have to enter a write speed of no more than about 23kS/s and then a minimum of about 800 samples to write. Otherwise I get the following error with LabVIEW:
Error -200621 occurred at WriteAO_MAIN_FILE_TestStand.vi,
Onboard device memory underflow. Because of system and/or bus-bandwidth limitations, the driver could not write data to the device fast enough to keep up with the device output rate.
Reduce your sample rate. If your data transfer method is interrupts, try using DMA or USB Bulk. You can also reduce the number of programs your computer is executing concurrently.
Does anyone know why this could be happening? The target is to get the VI to run on as few datapoints as possible to get a quick repsonse once I change the amplitude.