Digital I/O

cancel
Showing results for 
Search instead for 
Did you mean: 

NI 9476 only DO0-DO8 are working

I have a NI 9476 in a cRIO 9025.  I've been programming an application and I noticed that if I wrote to DO13 I would alreays read a false value.  I could never set it true.

 

So I hooked up a 24V LED and wired the supply properly to see if the output was actually working.  It wasn't, and it turn out that only DO0-DO8 are working.  The rest do not even though I can read back the state I set in all the channels except for DO13.

 

The LED was the first time the NI 9476 has been connected to hardware.  Is this likely to be a faulty NI 9476 or perhaps a driver issue.  NI-RIO 15 is installed.

John

0 Kudos
Message 1 of 4
(3,536 Views)

Hi, I have a few clarifying questions:

 

Are you using the scan engine or the FPGA to access this module? What version of LabVIEW and Real-Time are you using?

 

I also just want to confirm, the NI 9476 has 32 DO, only the first 9 work? The rest, except for DO13, will read a true value, but still won't ouput a true?

 

Is it possible to measure the actual output from the DO?

 

Finally, could you post a simple version of your code where you are setting the outputs? 

Matt G.
Product Manager
National Instruments
0 Kudos
Message 2 of 4
(3,512 Views)

Hi Matt,

 

Yes, I'm using the scan engine and labview 2014 32bit.  I'm not using a scanned variable read or write.  I'm simply dragging the variables from the project explorer to the vi.

 

I've even wired a boolean true constant to the variable just to be sure I wasn't doing anything stupid.  But when I read it, DO13 stays stuck at false..

 

You summarized me correctly except that DO13 will always read false.  DO0-DO8 outputs are correct, but DO8-DO31 outputs are always off even though they read back true when I set them to true.

 

I spoke to an engineer this morning and he was going to have the RMA people get in touch with me.

 

John

 

 

 

 

0 Kudos
Message 3 of 4
(3,507 Views)

Yeah, that sounds like the best next step!

Matt G.
Product Manager
National Instruments
0 Kudos
Message 4 of 4
(3,484 Views)