LabVIEW execution priority/Yielding to the operating system

[DarkLordOfG]

Hello, I have an interesting problem. I am doing some image acquisition with a third party board. I do not have any "onboard" memory to buffer images, thus they are DMA'd into host memory (PING-PONG scheme is used). Things work well except in the following situation. I will be running my LabVIEW app and if I go launch another program (say windows explorer) the labVIEW program gets "behind" I can tell that it is trying to read from buffers that are currently being filled. It is almost as if LabVIEW says "ok have the CPU" to the OS. Is there anyway I can set the application priority to keep this from happening? The subVI that does the data acq is already in it's own execution system with a "time critical" priori
ty.

Thanks!

OK now the obvious...just don't launch windows explorer when the application is running. Well, that sounds logical, but this application will be installed in a plant site and often the unlogical happens.....

[Jeremy Braden]

I cannot believe that I figured this one out! Here is an example program in LabVIEW 6.1 that will allow you to change the Windows priority of LabVIEW itself on NT/2000/XP.


I would not recommend using this VI to the regular LabVIEW programmer. Essentially the argument for not changing VI priorities applies here but with greater mangnitude. Look in the LabVIEW shipping docs for "Using LabVIEW to Create Multithreaded VIs for
Maximum Performance and Reliability" for a discussion of these settings. You can find this by opening LabVIEW 6.1 >> help >> search the LabVIEW bookshelf. This launches a PDF of all the shipping docs--it is at the end. The next best place to look is here on the forum. There have been detailed discussions of the settings in LabVIE
W.