[SOLVED] J-Link stuck in bootloader mode, won't update

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  • [SOLVED] J-Link stuck in bootloader mode, won't update

    Hello,

    We have a problem with a J-Link Plus that we bought last year. Part number is 8.08.28, version is 10.1.

    Our problem is that the J-Link firmware fails to boot, so it falls back to a bootloader firmware that won't even accept USB connections, making it functionally useless. The only reaction we can get out of it is the first time we try to establish a connection with J-Link Commander, it'll detect that we need to update the firmware



    then the update seems to complete correctly



    but the new firmware fails to boot with the following message.



    Here are some text dumps of the logs found in the above pictures (for search discoverability and easy copying) :

    Source Code

    1. WARNING WINDOW
    2. J-Link V6.62a Firmware Restoration
    3. The connected J-Link is running in bootloader mode.
    4. This happens if no valid firmware has been found on the J-Link.
    5. Without a valid firmware, J-Link cannot be used.
    6. O.K.
    7. FIRMWARE UPDATE WINDOW
    8. New firmware: J-Link V10 compiled Jan 7 2020 16:51:47
    9. Current firmware: J-Link V10 compiled Jun 3 2015 BTL
    10. Starting bootloader... already started.
    11. Sending firmware data... OK (491520 bytes).
    12. Waiting for new firmware to boot...
    13. Waiting for emulator to detach... Timeout, assuming emulator has already re-enumerated.
    14. Waiting for emulator to attach... OK after 0ms.
    15. Firmware updated successfully.
    16. CONSOLE
    17. C:\Program Files (x86)\SEGGER\JLink_V662a>jlink.exe
    18. SEGGER J-Link Commander V6.62a (Compiled Jan 31 2020 12:58:42)
    19. DLL version V6.62a, compiled Jan 31 2020 12:58:08
    20. Connecting to J-Link via USB...Updating firmware: J-Link V10 compiled Jan 7 2020 16:51:47
    21. Replacing firmware: J-Link V10 compiled Jun 3 2015 BTL
    22. Waiting for new firmware to boot
    23. FAILED: Communication timed out: Requested 4 bytes, received 0 bytes !
    24. Could not read J-Link capabilities.
    25. Cannot connect to J-Link
    26. J-Link>
    Display All

    After this failed update cycle, the J-Link won't respond to anything, it just gets stuck on "Connecting to J-Link via USB...", which doesn't timeout even after a whole hour. When the J-Link is in this state, here is what the ShowEmuList command gives us:



    Of course, our actual serial number isn't 123456. If we unplug it and plug it back in, we're back on square one: needs to update, "successfully" updates, doesn't work.

    Speaking of plugging it back in, when we plug the J-Link into a computer, the status LED:
    • is solid red for a second;
    • blinks twice while still red, only lasts about a second;
    • switches to a rapidly blinking green which goes away very quickly;
    • ends up on a stable solid green.


    Here's a list of configurations we've tried:
    • 2 different USB cables for the J-Link;
    • 4 different computers on Windows (7 and 10);
    • different USB ports on a single computer;
    • connecting both with and without a USB hub;
    • manually changing the driver in the Device Manager;
    • different versions of the J-Link tools (some older, some newer).


    Is there anything else we could try, or does this look like an RMA? Any help would be appreciated.

    Many thanks in advance,

    Hugo M.
  • Hi Hugo,
    Thank you for your inquiry.

    From what we can see, the J-Link seems to be defective.
    Could you please provide us with the serial number of this J-Link?

    I am asking because the the S/N you have added to your forum profile is from a unit which is out of support and warranty.
    For such a unit we recommend to make use of our trade-in program:
    segger.com/purchase/trade-in-program/

    Best regards,
    Fabian
    Please read the forum rules before posting: Forum Rules

    Keep in mind, this is not a support forum. Its main purpose is user to user interaction.
    Our engineers will try to answer your questions between their projects if possible but this can be delayed by longer periods of time.
    Should you be entitled to support you can contact us via our support system: segger.com/ticket/


    Or you can contact us via e-mail.
  • SEGGER - Fabian wrote:

    Hi Hugo,
    Thank you for your inquiry.

    From what we can see, the J-Link seems to be defective.
    Could you please provide us with the serial number of this J-Link?

    I am asking because the the S/N you have added to your forum profile is from a unit which is out of support and warranty.
    For such a unit we recommend to make use of our trade-in program:
    segger.com/purchase/trade-in-program/

    Best regards,
    Fabian
    Hello Fabian,

    You are absolutely correct, I'd been given the wrong information about which device had stopped working. The serial number I provided in my profile was correct and is indeed for the (seemingly) defective 2016 unit. The one we bought last year still works perfectly fine. However, we do have another defective J-Link Plus from 2014, serial number 609300932: would this unit also be eligible for the trade-in program? It's completely dead and has been since before I joined the company, its status LED won't even light up.

    Before going forward with trade-ins and buying new units, I also need to double-check something with you. At least one of our units will need to be downgraded to an older version of the firmware, as per one of our subcontractor's instructions for managing and debugging the software they made for us. The exact version we need to go back to is 4.96m – we still have the setup files, no problem there. As much as I've read in the user guide that downdating is not recommended, should we still be able to do it in theory, or are the newer units absolutely incompatible with pre-5.0 firmwares?

    Thank you so very much,

    Hugo M.
  • Hello,

    However, we do have another defective J-Link Plus from 2014, serial number 609300932: would this unit also be eligible for the trade-in program?
    Yes.

    Regarding firmware downgrade:
    You cannot perform a downdate of the J-Link V10 firmware using V4.96m because this version does not support the J-Link V10 firmware.
  • Hi,

    We will consider this thread as closed now.

    Best regards,
    Fabian
    Please read the forum rules before posting: Forum Rules

    Keep in mind, this is not a support forum. Its main purpose is user to user interaction.
    Our engineers will try to answer your questions between their projects if possible but this can be delayed by longer periods of time.
    Should you be entitled to support you can contact us via our support system: segger.com/ticket/


    Or you can contact us via e-mail.