The TI E2E™ design support forums will undergo maintenance from Sept. 28 to Oct. 2. If you need design support during this time, contact your TI representative or open a new support request with our customer support center.

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS570LS3134: DCAN operation when the arbitration is lost

Part Number: TMS570LS3134

Hi,

Suppose the DCAN lost the arbitration;

Q1) How long does it take the DCAN retransmit the data again?

Q2) If the DCAN keep losing the arbitration, how long is the timeout period?
Is this defined somewhere?

Thanks and regards,
Koichiro Tashiro

  • Hello,

    If several CAN nodes want to transmit message at the same time, the message with the highest priority wins the bus arbitration. The lower the number of the CAN ID, the higher the priority. The value of "0" is the highest priority. If the node has finished sending all arbitration bits (message ID plus RTR) without loosing the bus arbitration, it will transmit the rest of the message.

    Q1: At this time all other CAN nodes (lost the arbitration) in the network will have switched to receiving mode, and will try to retransmit their messages when the bus becomes available next time. The shortest time is (control field + Data field + CRC field + ACK field + EOF field) * bit timing. 

    Q2: The high-priority message wins the arbitration and is transmitted, and is followed immediately by a low-priority message, unless, another high-priority message attempts to broadcast immediately following the same message. There is not timeout period.