How can I use `nrfutil` to make `dfu` packages that don't use a SoftDevice?

[qm3ster]

As per description, I don't understand how to make a dfu package that  writes the whole MBR+Application range and doesn't use a SoftDevice, for example out of a hex file such as \examples\zigbee\light_control\light_bulb\hex\nrf52840_xxaa.hex.

I've been able to `dfu` the whole hex into the --application sector above an installed SoftDevice, which is clearly not the right approach.

I am looking for the equivalent of j-programmers --chiperase as opposed to --sectorerase, with the obvious distinction of leaving the bootloader intact.

I am on  Ubuntu 18.04 and Windows 10.
My hardware is a nRF52840.
I use the latest nrfutil (from pip, but it seems that there isn't a newer release on GitHub)

Answers such as this one don't provide enough detail for my level of familiarity with the ecosystem.

[Hung Bui]

Hi Michail, 

What exactly you want to update ? If you want to update just the application (no softdevice) you can just use --sd-reg 0x00 and don't provide softdevice hex. 

The MBR can't be updated with DFU. MBR need to be flashed by a programmer.