Bootloader settings backup in SDK 15.1.0

[Adrian Eggenberger]

Hi

I've migrated some of our code to the SDK 15.1.0. One of the new features in the bootloader seems to cause some problems right now.

I was able t build a project and a new bootloader based on the SDK 15.1.0, but now after a few updates it seems that there is a vaild bootloader settings backup in the flash that always overwrites may new written bootloader settings for a new application. 

Steps to reproduce:

- build secure bootloader and application based on SDK 15.1
- do some updates over DFU
- program a new application by uVision and  write the new build bootloader settings built by the nrfutil.

Now on startup the comment in the log of the bootloader implies that the bootloader settings are considered as invalid and are overwritten by the backup. Is this a common issue? How can it be resolved?

Regards Adrian

[Adrian Eggenberger]

Hi Aaron

Thanks for the detailed analyzation. I totally agree with your findings and your conclution that the backup needs to be invalidated or written with the download. I adapted your recommendation in my solution and it works perfectly.

Maybe a short addition concerning the halt of the CPU. I don't use this normally, but in this test i used it to stop the cpu to prevent that it starts after programming before i could setup the RTT viewer. It seems to work, but wouldn't use it normally.

Regards Adrian