Using DAQmx and digital outputs

[Marc Bassett]

I am trying to read 2 channels using DAQmx and I also need to be able to switch one of the digital signals. However, when I try this, it says it is unable to do this since the board is already being used. Is there a way I can have both?

[Marc Bassett]

Here is the code. Basic idea is that it starts recording the voltae across a resistor and a load cell at the same time, then when the start button is pressed, an electrical load is applied to test the disbond time of an epoxy. The electrical load is either constant, 5 Hz square pulse, or 0.5 Hz square pulse. The switching is controlled by a relay, which is controlled by a digital output. I am unable to both read in and control the digital out at the same time.

[Sean_C.]

Hello Marc,

Are you running any other applications when you run this VI? From what I could see, this VI should work. What is the exact error you are getting? Does it have an error code?

If you could edit this VI so that it only performs the Analog Input and the Digital Output, then I will run it and see if I can reproduce your error. Currently, I cannot run the VI because of the VISA communication.

Regards,
Sean C.

[Marc Bassett]

Sorry it took a while, but I've been busy with other things. Here it is with all VISA commands taken out. If there are still some in there, just get rid of them, no big deal, I got rid of the important ones.

[Dennis_Knutson]

You are using DAQmx and traditional DAQ at the same time. I don't think that's allowed. Why don't you try replacing the traditional digital out functions with DAQmx digital I/O functions and see if that works.