• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Subscribers 33 subscribers
  • Views 478 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

TCAN4550: The procedure to cancel a FIFO method or Queue method transmission request

Shinichi Inoue
Guru 21701 points
Part Number: TCAN4550

Tool/software:

Dear Specialists,

My customer is designing TCAN4550 and has a question.

I would be grateful if you could advise.

---

Regarding CAN controller TCAN4550

Could you please provide the procedure to cancel a FIFO method or Queue method transmission request.

for example,

If I set up a FIFO memory with 5 elements and 3 pieces of data waiting to be sent are stored there, is it possible to cancel some elements (especially in the middle)?

Is it possible to cancel transmission by specifying the index number in the TXBCR register for any transmission method?
(Will there be any damage or inconsistency in the data structure inside the TCAN4550?)

Please let me know if there are any steps I should be especially careful about.

---

I appreciate your great help in advance.

Best regards,

Shinichi

  • 0
    TI__Mastermind 33340 points

    Hello Shinichi,

    The TCAN4550 uses the the CAN FD Controller IP called M_CAN developed by Bosch, so I will refer you to the M_CAN User's Manual (Link) published by Bosch for detailed information about the M_CAN features. 

    A message can be cancelled by setting the corresponding bit in the TXBCR bit and the device should recalculate the FIFO indexes without causing issues with the other messages pending transmission.

    Regards,

    Jonathan

  • 0 in reply to Jonathan Nerger
    Guru 21701 points

    Hi Jonathan,

    I sent the Bosch manual you told me about to a customer, and received the following additional inquiry.

    Could you please advise?

    ---

    Regarding transmission cancellation

    In the Bosch manual, in "3.5.7 Transmit Cancellation" it says "Transmit cancellation is not intended for Tx FIFO operation."

    Does this mean that Tx FIFO cannot be canceled with the TXBCR register?

    Could you please tell me how to cancel Tx FIFO transmission?

    ---

    I appreciate your great help and cooperation.

    Best regards,

    Shinichi

  • +1 in reply to Shinichi Inoue
    TI__Mastermind 33340 points

    Hi Shinichi,

    The TCAN4550 uses the Bosch MCAN IP without modification, so I don't have any additional information that what is provided in the MCAN User's Manual. 

    Section 3.5.3 states:

    I do believe that transmission cancellation with a TX FIFO is not intended due to the way the Get and Put index values are handled and cancelling messages can make this more difficult than when dedicated buffers or a Queue is used due to the independence of the TX buffers.  But I don't think TX cancellation it is prohibited with a FIFO either. 

    Regards,

    Jonathan

  • 0 in reply to Jonathan Nerger
    Guru 21701 points

    Hi Jonathan,

    Thank you for your reply.

    I'll share your answer with the customer.

    When the customer has an additional question, I consult you again.

    I appreciate your great help and cooperation.

    Best regards,

    Shinichi

  • 0 in reply to Shinichi Inoue
    TI__Mastermind 33340 points

    Hi Shinichi,

    You're welcome.  I will keep the thread open if there are follow up questions.

    Regards,

    Jonathan