Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

  • State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 30 subscribers
  • Views 207 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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

Koichiro Tashiro
Mastermind 22110 points
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

  • 0
    TI__Guru**** 192196 points

    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.