Bootloader Update with new size over BLE DFU service

[Dominik Eugster]

Hi

Is there a possibility to update the bootloader himself over the BLE DFU?

I have a new bootloader with a bigger size (MemoryMap changed) and I am wondering if I can upload old boards with the small bootloader over BLE DFU with the Nordic nrf Connect App, because there is under SelectFileType (Bootloader). Is this possible only if the size and memory map is equal or even if the size is bigger?

I checked if I can download te new Ditribution Packet (ZIP) on the old device with the old small bootloader, and yes, its possible. The application is new but the bootloader is still the old one. Even after Powereset the application is running wit the old bootloader, this makes me a little bit confusing, ow is this possible?

See: https://devzone.nordicsemi.com/f/nordic-q-a/89328/ota-dfu-bootloader-memory-map-increasing-size-in-pca10056_s140_ble

Regards, Dominik

[Einar Thorsrud]

Hi,

You are right, an update zip consisting of application and bootloader is not supported. Generally, all combinations except for that is supported (see 4. Update softdevice and bootloader). Other than that, I do not have anything to add part from what is already in this post in the thread you mentioned.

[Dominik Eugster]

Ok thanks.

But why is there written that the APP + SD + Bootloader is possible?

In this post they say this is impossible, but maybe I understand something wrong?

Einar Thorsrud said:

this post

[Einar Thorsrud]

In this case, the DFU master (like for instance nRF Connect for mobile) split the update in two automatically. First BL + SD is updated, and then the app is updated as a separate operation.

[Dominik Eugster]

But this split has to be done with a special App or the normal Nordic nRF Connect will do? If so, how to create the zip wit the BL+SD+APP? all with nrfutil pkg generate in a combined file? thanks

[Dominik Eugster]

I got the reply:

Invalid combination: use two .zip packages instead.