Flashing an F18

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  • I have a DT No.1 F18, and I just came across the Bangle, which looks a lot alike. Can I flash Bangle firmware on my F18? If so, how?

  • Hi,

    Yes, it's the same hardware, so you can flash Bangle.js.

    I can't find it right now, but on this forum there are some earlier discussions about flashing firmware.

    But basically:

    • Wireless firmware updates are possible, but very difficult and can break the watch. It requires multiple flashes with a patched bootloader, new softdevice, and finally the firmware.
    • It's much easier to just open the watch (https://www.espruino.com/Bangle.js+Disas¬≠sembly) and then attach an SWD programmer and program it using the programming header
  • Thanks for the response Gordon! I'm assuming a binary isn't available?

  • Not a full binary including the bootloader - but literally all you need is to follow the instructions in the GitHub repo, then run BOARD=BANGLEJS RELEASE=1 make and you'll get one.

    If you've got an nRF52DK attached for programming then run BOARD=BANGLEJS RELEASE=1 make flash and it'll even program the watch

  • If you don't want to open it then you need to build your own softdevice+espruino bootloader dfu upgrade package. This is the missing part. 3 steps = 1. update existing buggy bootloader with fixed one (there is package for that) 2. softdevice+bootloader package you make - this will upgrade from SDK11 to SDK12 and espruino bootloader 3. ordinary bangle firmware zip

    So if you build from source as @Gordon suggests above, you either flash it over SWD via nRF52DK (or $2 stlinkv2 clone) and you are done with all 3 steps or you learn how to make softdevice+bootloader upgrade package and do 3 steps. If you are lucky and won't brick it, your device stays closed. If not you need to open it and use SWD. In both ways you need to build from source as mentioned above.

  • I'm assuming a binary isn't available?

    No. Just buy bangle if you can't be bothered to learn and build it from source yourself :-)

  • Thanks for the help!

  • I've looked everywhere, but I must be missing it. Where are the SWD points inside the watch?

  • They're under the display - you have to lift the display up and separate the little bit of grey foam that's in there

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Flashing an F18

Posted by Avatar for user126639 @user126639