Loading nRF Connect SDK app via UART using nRF5 SDK secure bootloader

[AntonZ]

Hi,

we are facing an issue of loading the application written with nRF Connect SDK to the nRF52840 which has nRF5 SDK's secure bootloader.
Update process should be performed by another MCU via UART (so two files are used for a single update: init packet and the image itself).

Based on my request posted previously, we decided to use the nRF5 SDK's bootloader.

Now, as I can see the output of the nRF Connect SDK is a single binary, yet the bootloader expects two files.

Since the bootloader and all application logic (of another MCU) is already implemented, is there some easy way to be able to send updates to the target Nordic chip?

[Hieu]

Hi AntonZ,

May I ask why you want to implement the bootloader in the nRF5 SDK? It is possible, yes, but I don't know whether that's the best option for most use-cases or not.

In any cases, if I understand the situation right, the bootloader is custom made by you, so I don't really know the background why it expects two files and am not sure how to help you with that.
I know the bootloaders provided in the nRF5 SDK can update the application using one single binary file just fine.

Hieu

[AntonZ]

Hi Hieu,

No, I might've put the wrong explanation: the bootloader is taked from nRF5 SDK (secure bootloader) which is triggered by another external MCU.

Two files I'm talking about are: 1. Init packet; 2. FW binary.

Both files are normally generated by nrfutil. But, as I understand, nrfutil can't generate such package for the app created with nRF Connect SDK.
So, how is is possible to send such application to the secure bootloader?

Thanks,
Anton

[AntonZ]

Hi Hieu,

I've replied, yet not to your response, sorry. 
Can you please comment below?

Thanks,
Anton

[Hieu]

Hi Anton,

I see. nRF Util should still be able to generate such a package for the app created with nRF Connect SDK (NCS). Please give it a try.
Note that you might have to change the DFU package type to SoftDevice, because the NCS application starts at 0x1000, where the SoftDevice starts in the nRF5 SDK.

By the way, if you are not heavily invested into this yet, I still recommend you consider if the nRF Connect SDK solutions are feasible for your project.

Regards,

Hieu