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Reading XNET values with NI 9862



I'm trying to read CAN messages using XNET vi's. I run a cRIO RT with an NI 9862 card. I've created an XNET session to read a single message but no data is coming through.


The dbc file has been supplied from a customer that we need to be able to communitcate with an ECU. Using Busmaster I can read messages from the ECU without a problem. I don't get any data coming through on XNET using VI's and I dont see anything at all on the XNET Bus Monitor.


Any ideas on what I could try on the XNET side? 


I'm using XNET 15.0, LV14 and NI RIO 15. 



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Message 1 of 8

Have you compiled your fpga and connected to the crio?


If possible can you post your Project/VI.

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Message 2 of 8

Have connected the suply voltage to the c-module? 

Message 3 of 8

Yes to both. Have run an FPGA blank bit file and the C-series module has 24VDC supply. I've tried using XNET Bus monitor launched from NI-Max and it's blank. 

I get no errors when using XNET vis on the RT target and it seems to be reading the default value for the channels (checked this by changing the default value in the dbc configuration). 


My CAN knowledge is pretty basic so am stumped by this. 

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Message 4 of 8

Can you show us your project or a sample project? 


It is far easier to view some code, to understand what you are doing. 

Also how are the RIO configured in hardware? 

In what slot is the XNET module located?  


edit: What cRIO are you runing the code on ?

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Message 5 of 8

The original setup run on a cRIO-9035 in slot 4.


I've moved from the cRIO and connected the NI 9862 to a cDAQ-9171 (1 slot USB) card. I've attached a sample project for the cDAQ card with a VI running single Input and single Output session with 1 signal in each to run on the cDAQ unit. I can't attach the dbc file as it contains customer information. 


No changewith this setup either. The LED's show solid green/solid red. As soon as plug into the ETAS card I can see bus traffic.  


During the last 24hrs I've also tried different cables, power supply, connecting COM to Pin3 and Pin6, laptops, XNET/CRIO versions. 






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Message 6 of 8

Hi DavidT,


It seems to work fine to me, all I've done is create the sessions at runtime.


XNET Example.png

 Can you view can traffic in the bus monitor in MAX now?

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Message 7 of 8

Hi AO1,

Unfortunately same outcome. No errors, no data on the bus and LED's steady green/steady red.


I have now purchased a replacement card (NI 9853) to see if it's the 9862 card that's faulty. 



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Message 8 of 8