Secure DFU: Bootloader Settings

[tejaChintalapati]

Hi,

I am trying to create a combined Bootloader + Bootloader Settings + Application hex file to flash the same into the devices during the production.

Bootloader Project:

pca10056_uart

Bootloader Settings:

nrfutil settings generate --family NRF52840 --application Firmware_PD52840V1R1.hex --application-version 0 --bootloader-version 0 --bl-settings-version 2 bootloader_settings.hex

Please note that I didn't give --no-backup as a parameter when creating settings.

Merging Files:

Bootloader and Settings

mergehex --merge secure_bootloader_uart_mbr_pca10056.hex bootloader_settings.hex --output BL_And_Settings.hex

BL+Settings and Applcation

mergehex --merge BL_And_Settings.hex Firmware_PD52840V1R1.hex --output finalMergedFile.hex

I noticed that, this is just updating the Bootloader settings in bank_0 and bank1 is filled by null. As the BL checks for the settings in Bank 1, even with the valid applicaton present, the BL isn't jumping to the application.

May I know what should I do to get the BL settings in Bank1?

[RVM]

Hi

I do not understand why the proposed solution 'fixes the original problem'.

My understanding is that if I program a softdevice to the board, it should ALSO program the MBR at address 0x0.
And it is also my understanding that one does NOT need to rewrite this MBR to support a secure bootloader/DFU module placed at another location in the flash memory map.

Cheers

RMV

[Vidar Berg]

Hi,

Your understanding is correct, the MBR is included in the Softdevice binary (0x0 - 0x1000), and it's never rewritten during DFU. OP had an application that didn't use the Softdevice, and therefore had to program our standalone MBR binary to support DFU.

Cheers

Vidar

[RVM]

Thanks Vidar

That makes perfect sense.

Cheers

RMV