Digital I/O

Showing results for 
Search instead for 
Did you mean: 

For checking on working of NI 9476

Go to solution

To check working of NI 9476 installed on cRIO-9063,

I tried digital output used by LabVIEW2015, 

after wirinfg the COM port and DO#0 of the NI 9476 to an oscilloscope.
But I cound not see any output response on the oscilloscope.
Is there something wrong with my wiring?

I checked the outputs on an oscilloscope in both DC and AC mode.
DO#1 to 31 ports was also checked and there is no response. 
The NI 9476 is a D-SUB type, and I connected each pin by clipping.
In addition, I connected a resistor (10 or 150ohm) between the DO pin and the oscilloscope. That was no response.
Finally, I connected the Vsup port and Com port to the oscilloscope and I expected that the step waveform would be output.

But there is no change.

I can see analog output signals via NI 9264 installed on cRIO-9063.

I suspect NI 9476 initial defect.


Thank you


0 Kudos
Message 1 of 5

Dear jennitro,


Did you connect the resistor from the beginning? Did you try without resistor?]




0 Kudos
Message 2 of 5
Accepted by topic author jennitro

The NI-9476 requires an external power supply to work (6 - 36 V)

If you connect the oscilloscope to Vsup and COM and got nothing check your power supply with a DMM

0 Kudos
Message 3 of 5

Thank you, anasei


Yes. I did connect some resistors with various values at first stage for this checking, and also I check this wroking without  resistors.

Your point is correct.
Because I was suspicious of that point too.




0 Kudos
Message 4 of 5

Thank you, Antoniooh


I finally reached a conclusion you pointed out.

As you said, an external power supply was needed for this module working. Thank you , again.


My degital signal detecting device individually provids power to a digital channel and individually shorts power made the digital signals.
On the other hand, the NI 9476 shares the power supply to Sup port with all ports. This means that all digital channels on my device detects the same signals. I think the 'Relay Output Module' was better for my intend.




0 Kudos
Message 5 of 5