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usb 8451

Hello. I tried using the USB-8451 Test Panel. I want to swith the DIO lines, but only BIT 0 works. None of the others respond. In fact, I tried using them as inputs, but they still don't work. These DIO lines have never been exposed to high voltage, or any kind of contention because this is the first time using these lines. I am not sure if my problem is in software, or the hardware. Am I doing something wrong? Please be advised that one DIO line works, so I must be doing something right.

 

Thanks, Richad V

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I forgot to include the file.

 

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Nothing seems to stand out as incorrect with your code. To make sure it isn't a hardware issue, I recommend making a simpler example if possible. Try creating a VI that only uses the 845x DIO Write Line VI with controls wired to its inputs, and see if you can get line 1, 2, and 3 to work alongside line 0.

 

Regards,

 

Ryan

Ryan P.
CLA
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Hello Ryan. My code? I downloaded this from the website. I thought I mentioned that. This is not my code; Sorry if that isn't clear. This is why I don't understand why it doesn't work.

 

I recall a problem if I had used this board in I2C or SPI mode where the DIO lines are used as chip selects. I think the unit is configured to use those lines a chip selects. I don't know how to fix this though.

 

Thanks, Richard V

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Hello to anybody that is interested. I found out what my problem was. The terminal block on the 8451 are not really connected until the screws are tightened down. The software example given works perfectly.

 

Thank you, Richard V

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