Generating CRCs per SAE J1850

[h_yong]

Hi,

I'd like to know if VeriStand/XNET's automatic frame processing is flexible enough to support the SAE J1850 8-bit CRC. It looks like it may be, but can anyone confirm? Thank you.

[Joe Steak]

Hey Hyog,

VeriStand is a very flexible platform as you alluded to. You are able to make Custom Devices to extend the capabilities of VeriStand so that it can interface with additional hardware. I believe that you would need to make a custom device to work with SAE J850.

Here are some resources to help you get going.

NI Community on NI VeriStand Add-Ons with templates and getting started tools

Building Custom Devices for NI VeriStand

Custom Device Developer’s Guide

NI VeriStand Help

Hope this helps you out!

Joe S

Applications Engineer

National Instruments

[h_yong]

Hi Joe,

Thanks for the response. I am sure that it can be done with a custom device, yes, but I was wondering if the built in functions already support it. It looks like it probably can be configured to match the SAE J1850 CRC, but I thought I'd ask to see if anyone can confirm. Thank you.

[Joe Steak]

Hey Hyog,

Looking further into this, it is definitely not supported in the built in functions. There is no NI hardware that interfaces with J1580 bus. It may be difficult to make it work with VeriStand but you may be able to use some third party devices and drivers. A company called Dearborn sells a hardware interface called Gryphon which supports the interface. One of National Instruments Alliance members, VI Engineering created a Gryphon toolkit which allows you to use J1850 in LabVIEW.

Hope this helps.

Joe S

Applications Engineer

National Instruments

[h_yong]

Hi Joe,

I'm actually not too concerned with the hardware details of the J1850 bus. I am using the PXI8512/2 card, and it is working fine. My main question is whether the CRC method specified by the J1850 is supported in software by VeriStand's 8-bit CRC generator. I think it probably is but I'd like to confirm. Thank you.

[timtamslam]

Hey Hyog,

Based on this documentation,

https://www.ni.com/docs/en-US/bundle/veristand/page/configure-crc-counters-outgoing-can-frames.html

At the very bottom it says,

"NI VeriStand supports CRC-8 and CRC-16 length polynomials."

Based on that message, I would say that it supports CRC-8 polynomials but it seems that you would still have to do the additional Custom Device for J1850. I would need to do a bit more research to say confidently that what you're doing will work because as you might expect, the J1850 protocol has not been extensively tested in VeriStand.

Hope this helps!