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TMDSCNCD263: Can communication not working if multiple PDUs are mapped to single HOH

Part Number: TMDSCNCD263

we are using Can driver from MCAL_AM263x_09.00.01.00 package

We are doing a stress test by assigning maximum PDUS to each HOH and checking the communication scenarios.
During testing we find that, for the HOHS where multiple PDUS are mapped, some Rx PDUS are lost while reception. There is no specific pattern to it.
We have configured the value of CanHwObjectCount as the exact number of PDUS mapped to that HOH.

Could you please let us know if there are some configuration to be taken care if we map multiple PDUs to HOHs. Also let us know if there is any restrictions to number of PDUs that can be configured for HOH.



  • Hi Sivaram,

    Sorry, I did not understand your question fully. Please provide more details.

    When you said multiple PDUs does it mean you expecting multiple CAN message Ids into 1 receive mailbox object?Please share your configuration as well.



  • Hello Sunil,

    We were able to resolve the issue. Let me explain the scenario.

    We have some stress tests , which involve assigning multiple PDUs (multiple CAN message IDs) to single HOH, some of the messages were getting lost.

    The definition of the configuration parameter CanHwObjectCount states "

    Number of hardware objects used to implement one HOH. In case of a HRH this parameter defines the number of elements in the hardware FIFO or the number of shadow buffers"

    However we cannot assign the exact number of the Rx PDUs configured to a single HOH for parameter CanHwObjectCount.

    The derivative has a limit of maximum of 64 buffers and 32 HOH only. So if we are using all the HOH, then the parameter CanHwObjectCount can be configured as 2 for all HOH so that the maximum limit cannot be exceeded.

    This limitation is not mentioned in the definition or there is no validation check for configuration corresponding to this max limit. If the project configured the CanHwObjectCount such that the sum of  CanHwObjectCount for all HOH  exceeds 64, frames will be lost and test cases will fail.

    The validation check or documentation has to be done so that we can avoid the scenario of losing messages in the testing.

    Please let me know your comments.

  • Hi Sivaram,

    Please correct me If I understood wrongly.

    Our Can configurator is not reporting an error if CanHwObjectCount > 1(FIFO) and the total count is > 64 right?

    I do see if you allocate CanHwObjectCount to 1 i.e. buffer and total count is > 64 our configurator reports error.

    So issue is only with CanHwObjectCount > 1 and total is > 64 right?


    Sunil Kumar M S

  • Hello Sunil,

    Yes issue is when CanHwObjectCount > 1 and total is > 64. There is no validation check to report error in this scenario