Running two PCI boards at the same time

[dan240]

I am running an array of transducers that require me to run two PCI boards installed in my PC to get the required number of channels. I need to be able to take data from both cards at the same time, at high sampling rates >10000S/s. If I try to take data from two boards LabVIEW takes data from the first board and after completing it then goes on to take data from the second board. Is this possible using a simple "Export to Spreadsheet.vi" The data speeds and accuracy seem fine the data is just not being taken from all channels all at once. I am hoping for a software solution.

[RIO-Todd]

I believe that you are wanting to write the data from both devices to file at the same time. What if you took the output of the two AI Read VIs (for the two devices) and build them into a large array. Then you could take that large array as an input to a simple VI like the 'Write to Spreadsheet File VI.'

By using the 'Build Array' function, you would use the data-flow aspect of LabVIEW to ensure that the data from both devices will be written to file at the same time. I have included a simple example of this (without data acquisition) below for a reference (used LabVIEW 6.1). The example has two for loops running in parallel where each is generating a random number per iteration. Run the program with highlight execution on (light bulb on block diagram)
and watch how the data is not written to file until both arrays are received by the 'Build Array' function. I hope this helps.

Todd D.
Applications Engineer
National Instruments