AnsweredAssumed Answered

FlexCAN multiple ID Rx

Question asked by Robert York on Aug 20, 2015
Latest reply on Aug 31, 2015 by Robert York

I'm using MQX 4.1 and the FlexCAN drivers, and I'm running into a problem where my device needs to receive CAN messages with different ID numbers, and so far, I'm getting very sporadic behavior.

 

The FlexCAN demo has a mailbox mode and FIFO mode, and I was using the mailbox mode fine, with the CAN ID I was looking for. However, when I wanted to have it receive messages with a second ID, I ran into issues. I could change the ID fine by changing the RX_identifier  in the example code, but I've not been able to find a method to get it to accept more than one. I've tried duplicating the code and changing the variables for a second mailbox, but now I seem to randomly be receiving one of the two different IDs. I'll send one of the IDs, and it will receive them fine for 2-4 messages, then it will no longer receive them. If I send the other ID, it will receive that for another few, then stop until I swap IDs again.

 

I tried changing it to FIFO mode, and now it's not receiving any messages.

 

Given the general lack of documentation, I'm really at a loss on what to try next, or how to fix this. Any help or examples of working code that receive more than one ID on a message would be appreciated.

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