Reading a DAQ board from several VIs

[sergey 671]

Hi!

I have a 6071E DAQ board. For design considerations, I'd like to perform buffered DAQ reads from several VIs concurrently, while several VIs may read the same board channel (all at the same frequency). Eventually all VIs must get the same data, but they run independently. The number of VIs is defined in run-time, but it's known before the acquisition starts.

(How) Is it possible ?

Thank you,
Sergey.

[mikeporter]

The only way to guarantee that all data clients get the same data is to have it measured in one place and have that acquisition engine "publish" that data using something like a cache VI. Multiple VIs can not read the same acquisition buffer at the same time. Remember, reading the buffer removes the data from it.

How fast are you needing to sample? How many channels? How many points are you reading at a time? What are you doing with the data? Does the acquisition need to be continuous?

This could be tricky, but it doesn't seem impossible.

Mike...
mporter@arielcorp.com

[Dennis_Knutson]

I'd look into having an acquisition VI that publishes the data using Datasocket. Only one VI at a time can directly access the hardware.