Digital I/O

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Multiple Digital Output Using DAQPad-6507

Hello, I'm using DAQPad-6507.
I made a VI using several "Write to Digital" in a case structure, in order to write 6 ports (0,1,3,6,7,9) at the same time.
However, port 6 cannot be written. So, i changed to port 4 from port6, then port 3 wasn't written.
I cannot understand why this happening...
Plz help me to solve this problem.
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Could you please post your VI so that we can get a better idea of what you are doing?



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Here is the VI i used...
Thanks ahead..
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Because the DAQPad-6507 is a 8255 based device, the digital lines on ALL of the ports are reset when you change the configuration one digital port.  This may be the cause of the undesired behavior in your VI.  For more information on this, read the link below.

Why Do All My Digital I/O Ports Reset When I Configure One Port?

You should not use multiple Write To Digital Port VIs when writing to more than one port.  Instead, you should call each DIO Port Config function (one for each port) all at the beginning, and then call your DIO Port Write functions.  I have attached a screenshot of what this should look like for your program.

Hope this helps!

National Instruments

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Thank you very much... i'll try to do so....
Thanks a lot.
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