Working with Labview RT and NI-CAN

[EricHettler]

I am attempting to use a CAN bus (PXI-8464) in a real time target to accept CAN signals from an external source.  It did not seem to work, so I decided to test it using the I/O examples found in Labview.  I connected the 2 ports on the bus together with a CAN cable to output through one ond input through the other.  I am using the project file attached in the .zip file.  I have FTPed the example.ncd file to the target.  I can connect to the target and I get no problems when I deploy all.  When I try to run the files I get the attached error.  I have gotten this approach to work in the past and I am not sure what I am doing wrong this time.  What is the problem here?

[EadieU]

Your issue might be resolved by this KB article:

Error -1074388479 With the NI-9853 Module for CompactRIO

This specifies the CompactRIO and the 9853, but you should follow the same instructions.  

If this does not resolve it, does your RT system have the same version of the CAN driver as the Windows development computer?  You can check this in MAX. 

If it has the same version, when you have gotten this approach to work in the past, was it on this same RT system and development computer? 

[EricHettler]

Ok, I'm getting closer so a solution.  It was definitely a CAN version error.  The RT machine and the host now have the same version of NI-CAN (2.6.2).  I am still having an issue though.  Now both of the VIs deploy correctly on the RT box, but I keep getting an error (attached) from the output VI.  If the input VI is set to CAN0 and the output is set to CAN1, nothing seems to be transmitted when I start the VIs (I am always deploying the input VI first).  If the input VI is set to CAN1 and the out VI is set to CAN0, then the first value seems to pass through (the value of the input becomes the starting value of the output) but then nothing after that.  I will still get the same error after a few seconds.  I have already verified that the VIs work correctly on the RT target if I do it through windows (it is a dual boot machine).  The only other thing I can think of is that I changed it the version of DAQmx on my host machine but not the RT target.  Could this effect it or can you think of another reason this would happen?

[Gibson]

NI PXI 8464  has as default different transceiver settings (Highspeed and LowSpeed)

 For port to port tests you need to change them to identical settings

Hope that helps.

[EricHettler]

To add to my last post, they both now have the same version of DAQmx (8.9.5) and the same thing is happening.

[EricHettler]

How do I change them on the RT target and what would I change them to?

-Eric

[Gibson · Accepted solution]

you can change the default e.g. in MAX >> Utilities >> NI-CAN >> RT Hardware Configuration

[EricHettler]

Wow, I can believe I didn't remember to do that.  That got it working.

-Eric