DFU on nRF Connect SDK by Random Flash Write

[loquat]

I would like to use the DFU from the nrf connect sdk.

After researching the API, I found out that dfu_target_write() can only write to FLASH in sequential format?

In our project, we want to randomly write DFU images to FLASH in order to transfer them over an unreliable transmission path.

Is such a method provided?

[Vidar Berg]

Hi,

It should be fine to not store the data sequentially as long as it all gets stored in the end. But you will probably need to use the regular flash API, and not the Stream Flash API used by dfu_target_write(). There aren't any DFU examples that do non-sequential writes as far as I can tell.

[loquat]

I believe the dfu_target_xxx API does a lot more than writing the image to FLASH.
It may be possible to write a DFU image to FLASH using the FLASH API, but I don't know the process to prepare the DFU.

By the way, we have independently incorporated and operated the same functionality into the nRF5 SDK.
We want to use this functionality that we implemented in the nRF5 SDK in the nRF Connect SDK as well.

[Vidar Berg]

You can read about the DFU target library here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.4.2/nrf/libraries/dfu/dfu_target.html. But for your case, I think it would be easiest to start with the smp_srv sample (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.4.2/zephyr/samples/subsys/mgmt/mcumgr/smp_svr/README.html#smp-svr-sample) and see how it uses mcuboot.c and flash_img.c to place the update binary in slot 1. 

[loquat]

I see. I will try.

Thank you