Thingy52 DFU fails with message "FW version failure (Code = 5)", using nrfutil and nRF Connect

[Till]

Hi all,

I've got a single Thingy:52 (FW v2.1.0), and no DK. I'm trying to upgrade its firmware through nRF Connect on Android, but keep on running into a FW version failure (Code = 5) error whilst doing the DFU.

Can anyone enlighten me whether the following workflow is currently supported, and if so, what I am doing wrong? Any hints will be much appreciated and I'll update my question if you need any further details.

Abbreviations:

• APP - my firmware application code
• BL - the bootloader
• SD - the s132 Soft Device

The APP, BL and SD have been taken or compiled from this Github commit of the Thingy SDK v2.1.0.

Suggested Workflow (paths truncated for readability):

1. Compile the APP, cd <ProjectRoot>/project/pca20020_s132/armgcc && make -j. This builds nrf52832_xxaa_s132.hex.
2. Generate BL settings, nrfutil settings generate --family NRF52 --application <APPDir>/armgcc/_build/nrf52832_xxaa_s132.hex --application-version 1 --bootloader-version 2 --bl-settings-version 1 settings.hex
3. Generate key pair and compile the BL, cd <ProjectRoot>/project/bootloader_secure/pca20020/armgcc && make -j. This builds nrf52832_xxaa_s132.hex (same name as APP, but different hex content).
4. Merge BL with settings, mergehex -m <BLDir>/armgcc/_build/nrf52832_xxaa_s132.hex settings.hex -o bl_with_settings.hex
5. Generate DFU package, nrfutil pkg generate --application-version 1 --bootloader-version 2 --hw-version 52 --bootloader bl_with_settings.hex --softdevice <ProjectRoot>/external/sdk13/components/softdevice/s132/hex/s132_nrf52_4.0.2_softdevice.hex --application <APPDir>/armgcc/_build/nrf52832_xxaa_s132.hex --sd-req 0x98 --sd-id 0x98 --key-file private-key.pem thingy-dfu.zip
6. Upload thingy-dfu.zip to internal phone memory and perform nRF Connect DFU, which results in the following error: [DFU] Remote DFU error: EXTENDED ERROR [DFU] Details: FW version failure (Code = 5). See the full nRF Connect log here.

So supposedly something's wrong with my version numbers. I've tried all sorts of combinations, from APP=BL=0, to APP=BL=10.

Thanks!

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Update: The nRF52 DK has arrived and flashing, in order, the SD, APP and BL (merged with the settings file as per above) via nRFgo Studio on Windows works. For that I use the Segger debug connector as suggested in this answer, and modify the Bootloader to accept custom FW as suggested here, including the const modification.

[Bjørn Kvaale]

Hi Till, there's a makefile located under project\bootloader_secure\pca20020\armgcc in the Thingy FW. Is this fine or did you want to use the debug bootloader? I don't think you will need to modify the bootloader. This link explains what steps you need to take to make OTA-DFU work on the Thingy:52. In other words, this might be the reason you are getting the error.