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TTL signal output issue from NI9401

Hi everybody, I am having issues producing an output TTL signal from the module.


I can't seem to figure out what is causing the problem.  I am currently using the cRIO-9042 with an NI9401 module. The module is under Real-Time Scan Resources and I have configured the module properties to output for DIO7:4.  When I put a True signal to turn on the output, it stills remain False. 


Any help or advice on this particular issue will be greatly appreciated! This problem has been hindering my progress. Thank you!

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I cannot replicate the problem but I remember that some modules needs to use the start property. May be it is the same from this one.

(I suppose that you set the line like output).



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Can you please elaborate more? This issue is really troubling me. The logic is as straightforward as it could be. I just don't get why it is not working.

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I would avoid inserting the same digital node both in write and read mode in Labview. First you write a boolean value to the Digital port. Then you read from it, perhaps labview gets confused, because it seems like the mode is changing inside the VI.

Physically connect with a cable the Digital Output 6 to a Digital Input, e..g 3.

Then read this port (3) to see what its level is.


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