DFU update from SDK 11 to SDK 12 - app and bootloader

[Astalos]

Hi

I have working application on SDK 11, contained with bootloader, softdevice 130 and application using BLE. Is it possible to upload new application and softdevice from SDK 12 to exisiting via DFU? I know that legacy bootloader can not be replaced, but is it possible to upload everything else without bootloader?

[bjorn-spockeli]

Hi Astalos,

you are correct in that you cannot update from the Legacy Bootloader to the Secure Bootloader on the nRF51 Series if you have not allocated ~24kB to the Legacy Bootloader.

Yes, it is possible to update the application and SoftDevice so that they're up to date to the latest SD and SDK versions, but then you will have an unusable bootloader.

I recommend making the legacy bootloader from SDK v11.0.0 compatible with the latest SoftDevice by compiling it against the headers of the S130 v2.0.x. Then you can perform a BL+SD+APP update and you still have the DFU functionality.

Best regards

Bjørn