J1939 receive outputs incorrect values.

I am using the vehicle networking toolbox to recieve j1939 messages from a GPS device. The configuration is done using the .dbc associated with network and I have verified the configuration is proper. I am able to read the messages using the Vector Canalyzer software, however the values being output from the J1939 recieve block do not match. Are there some limitations to the j1939 blocks within the vehicle networking toolbox? It seems there is some issue within the block itself that is not exposed to the user.

Answer 1

[Shlok]

Hi Andrew,

I understand that you're encountering incorrect values from the "J1939 Receive" block, even though the configuration appears correct. The limitation arises because the block processes data strictly based on the DBC file, and if the transmitted messages don't fully match the DBC (e.g., in message length or signal packing), it may result in incorrect values.

A possible solution is to ensure that the transmitted message strictly follows the DBC format. Alternatively, you can initialize missing signals to default values using a script.

For further details on "J1939 Communication", refer to the following MathWorks Documentation link:

https://www.mathworks.com/help/releases/R2022a/vnt/j1939-communication.html