XNET Removes Priority from SAE J1939 Message Identifier...

[swbpnole]

I am currenty using LabVIEW 2015, and implemented a simple CAN loopback test to test the J1939 XNET capability. I noticed that XNET seems to be removing the message ID's priority. Example, I set the message ID to be 0x18C45671 with '0x18' slice containing the SAE J1939 message priority, it is received on the other side and displays as "0xC45671". Why is this? I have attached a picture for reference.

[swbpnole · Accepted solution]

Further reading in the NI-XNET Hardware and Software Manual for 2015 brought me to this:

"In standard CAN frames, the complete identifier is considered as the CAN message identifier;

in J1939, only the PGN determines the message. Frames with the same PGN but different

priority or source address are considered the same message." - chapter 4, pg 59.

I understand this but do disagree with X-NET implementation that removes the priority on the receive side (or is it just before transmission?). I would like it to stay but this is not a big deal I can live with it...