Overwrite Softdevice by application using Thread Secure DFU

[Nordic DevZone]

Hi everyone,

I would like to overwrite my SoftDevice wchich I don't use in my application. I found information about updates without Softdevice. 

Its possible to update application without SD? I would like to change start app address from 0x26000 (1st application which contains SD) to 0x1000 (after MBR - 2nd app without SD). 

I tried to prepare image pkg with sd-req 0x00

nrfutil pkg generate --hw-version 52 --sd-req 0x00 --application-version 60608 --application app.hex --key-file board_dfu_upgrade_key.pem customer-pkg.zip

I was able to download dfu image but BL didn't activate it.  

Could I overwrite SoftDevice by application via DFU or/and should I update BL too? 

BR

PB

[PBeS]

No, first BL was build with BLE support and flash via serial. 

[Vidar Berg]

Then the app will not be allowed to overwrite the Softdevice. From  the nrf_dfu_ver_valdation.c::sd_req_ok() check: