Cannot send and receive voltage commands

[zzzfreedom]

Hi,

I was using NI-cRIO 9022 with two modules (NI-9205 as input &NI-9264 as output) for more than 2 years. Recently the whole device got a problem of sending and receiving voltage signals. I created a simple VI that sends one voltage command from one output channel and reads voltage measurement from one input channel in a for loop. I wired the two channels directly. I used multimter to check the voltage output but NI-9264 did not sending out any voltage at all. NI-9205 did not work as well. I tried to restart the device, unplug and plug back the modules or creat a new project file, none of them worked. 

There is one thing noticable that, when the simple VI is running, if i go to the project explorer and deploy the VI there and hold the deployment progress information box on, everything works. But after I close it, the program shuts down again no readings from input channel. I have attached a screenshot of the simple program and how it works only when i hold the deployment progress box on.

I  am wondering if anyone has similar problems or knows how to solve it.

Thanks

Carl

[j_bou]

Hello zzzFreedom,

This is indeed a bizarre problem. Especially that fact that it works properly when the deployment window is being displayed. Just to clarify, when you say that the program shuts down, do you mean that the program stops working or that the program stops running?

When developing a real-time application, it is recommended not to acquire data in a while loop that is running as fast as possible. The scan interface engine can only acquire data at a maximum rate of 1KHz. It may be a good idea to slow down the acquisition rate using a timed loop or a wait function. This may shed light on the root of the problem.

j_bou

[zzzfreedom]

Hi j_bou,

I have reformated the cRIO and it now works. Thanks for the reply

Regards,

Carl