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DI and DO DAQmx tasks running in parallel

Hardware: NI-9403 in cDAQ-9178 chassis.


I've attached an example VI to illustrate what I'm attempting to do. I have an NI-9403 DIO module with which I'm trying to execute parallel DI and DO tasks. I get the following error when I attempt to run the attached code:


Error Code.png


I'm not sure if this is because I'm trying to do something that can't be done, or if it's my implementation that is causing the error. Any ideas or insight into what's causing this error would be very helpful.

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You need to use the vi "DAQmx Control" to reserve each task and when done use the same vi to unreseve

something like this:


don't have the same hardware but it should work for you i hope



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Thanks for the suggestion and sorry for the late reply. I tried implementing it, but I still get the same error.


I think my problem is I'm trying to do something that isn't possible with my hardware. I did some more research and found this article: Digital I/O Considerations for C Series Devices - NI-DAQ™mx Help - National Instruments. It says the NI-9403 is a serial digital I/O module and my cDAQ-9178 falls under the second row of the table. Footnote number 2 says "You can only do hardware timing in one direction at a time on a serial module." In my original VI, I was using the DAQmx Timing VI on the digital input task. If I remove that, then the VI executes with no errors. The explanation makes sense to me, but I could be wrong.

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