Sending a CAN frame with DLC > 8 using the .Net API (CanPort.dll)

  • Hi,

    I know it seems a bit odd but I'm trying to send a frame over CAN with the DLC being set to a value greater than 8.

    (I still expect the driver to only transmit 8 bytes.)

    As stated in your CAN driver documentation (Version 2.06, 2015-03-23), such values will silently be sent (despite actually transmitting only 8 bytes of payload).


    Now my problem is that your .NET API implementation does not accept any DLC parameter greater than 8 and does not transmit any frames on invocation. I.e. an errorcode/exception occurs.

    Can you think of a workaround that allows me to use your API and still send frames with DLC > 8 ?

    Maybe WriteRegister()/WriteRegisterRM() could do the trick ?


    I'm using an EFUSA9 w\ WinEC2013.


    Thanks & Best Regards

    Philipp

  • Hello,


    assume you missunderstood the statement in the documentation. Even if you set DCL=15 only 8 bytes are transmitted but for DCL 15 is transmitted. This limit is given by the HW.


    CAN FD (CAN with Flexible Data-Rate) is not supported at the time.

    But maybe on future HW.

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.

  • Hi,

    I got that the maximum transmissible payload is hardlimited to 8 byte. But still, I want to set the DLC to a value greater than 8. Of course, doing so won't extend the MTU, and I don't expect it to do so.

    All I'm looking for is to set the DLC to a kind of 'invalid' value of e.g. 10 and transmit only 8 byte of data.


    Nevertheless, I currently found that CanPort.Write(string tosend) accepts arbitrary DLC values without error and truly sets the bits on the line like given.

    If you know another method which spares the conversion from binary to ascii, please let me know.


    Best Regards

  • Ok, now i understood.

    you would like to transmit addional information using the 4th bit of DLC.

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.