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how to use ni 9401 to choose different channel to output pulse

i use cDAQ9172 and ni 9401, i put ni9401 in slot 5 and generate a pulse using counter. But i notice all 8 digital lines have output signal. I used counter0 and i thought there will be only output in CTR 0 OUT, that is pinout 19. Why from PFI0 to PFI7 i can capture the generated pulse. Is there any way that i can control which line shoud give output.  Because i need two output signals but i don't need them at the same time. There is no relation at all between these two signals. I just set an example. i use CTR 0 to generate a pulse meanwhile i connect pin19(CTR 0 OUT) and PFI7 as output to two different device. i don't want to send pulse to these two device at the same time,what i want is to have some control about them. For example, push a button pulse will be output in CTR 0 OUT , another button output will be in PFI7. Acturally i'm quite confused right now, if anyone has any idea about it, hope can give me some hint.


Thanks in advance.


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Hi zhiqin,


Noticed you never got a reply concerning this Discussion forum, Are you still having problemscontrolling which Digital lines are high and low? Do you mean that you are seeing the pulse train generation on all 8 digital lines? You should have absolute control over all the lines, but you must configure those lines to be input/outputs before (by creating virtual channels/tasks) to beable to specify the state of those lines. 


Let us know if you are still having problems with this.  And if you are please expand on what exactly you are seeing with maybe a screenshot of your code and maybe details on hardware configuration.


Thank you 

Charley Dahan

Global Account Manager
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Message 2 of 3

Hi Charles,


Thanks for your reply. Never mind. I have solved that problem. 

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