Serial bootloader / DFU without softdevice and crypto

[T IJ]

Hello DevZone,

On my board I have a nRF52810 and a nRF52840. I want to implement a serial bootloader for the nRF52810 and have the nRF52840 program it.

I have looked for example projects for DFU over serial and found only projects that have encryption built into the library.

Is there a example project available where I can use the bootloader / DFU without encryption? 

The nRF52810 does not use the softdevice, both devices are using the SDK 17.0.2, the nRF52840 does use the softdevice.

I'd preferably would use an example project but it should not be a problem if I have to write the bootloader / DFU myself.

Kind regards

[T IJ]

Vidar Berg said:

But why does it have to be done on the chip itself.  It seems like it would be a lot easier if you just generated the init packet together with the binary.

Protobuf is something we intent in using anyway so that shouldn't be an issue.

The reason we want to do it in the chip itself is that it will probably also perform DFU over Bluetooth to other devices. We want to probably use hex merge to merge multiple firmwares in one hex file for programming the main controller.

Instead of running the nrfutil every time we have a new version we prefer to only export the hex file and let the microcontroller create all required metadata