CAN bus breakdown after restart

  • Hallo,


    every time we connect a freshly restarted device on an existing and running CAN bus, the existing bus stops working correctly.

    Only after the CAN bus is open and initialized programatically, etherything works.

    After a reboot of the system the problem occours again.


    Now the question arises, what exactly happens on the CAN Interface after restart.

    Is there a way to let the CAN bus be disabled after restart, so it doesn't interfere with the existing bus and after connecting the board to the CAN bus the bus keeps working?


    Addendum: The cabeling should be fine, we tried different ones.

    The board runs on WindowsCE.

  • Hello,


    when did the trouble starts?

    Immediately after power on or at the time when CAN driver is loaded by the kernel (refer debug output, CAN prefix is "CID")?

    Which kernel and/or CAN version do you use?

    Which Bootloaders?


    Maybe ist is enough to specify initial baudrate via WCE Registry to your actual baudrate on your bus? Overall, which initial setting do you do in the good case ("bus is open and initialized programatically")?


    >> Now the question arises, what exactly happens on the CAN Interface after restart.

    Is there a way to let the CAN bus be disabled after restart, so it doesn't interfere with the existing bus and after connecting the board to the CAN bus the bus keeps working?

    << Hope the problem is resolved with the above suggestion, else we have to modify the driver or another componet which causes this issue. First we should locate origin.

    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.

  • Hallo and thank you for your fast reply!


    How can i figure out the versions of the kernel and bootloaders?

    Also i couldn't find the registry entry to set up the initial baudrate. Where can I find it?

  • Hello,


    >> Also i couldn't find the registry entry to set up the initial baudrate. Where can I find it?

    << Please refer the CAN documentation (note the registry path maybe HKLM/Driver/builtin/<boardname>/...): CAN Doc .All docs will find at our homepage->producs-> ... .


    >> How can i figure out the versions of the kernel and bootloaders?

    << You will find it in the serial debug output while booting (refer First Steps Doc Chapter 3).

    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.

  • Problem solved.


    Setting up the initial Baudrate as mentioned in section 6.2 of the CAN Doc solved the problem.


    Now the freshly started board can be attached to the CAN bus without any incidents.


    Thank you very much for the quick help.