Thread DFU

[Jay]

I want to program the firmware into a nrf52840 on our custom board to be the NCP and do the DFU over thread. I can not use the DK board and have the nrfutil load the firmware.

I also need to be able to change the thread masterkey.  Is the source code available as an example. Or a precompiled Hex file I program into the 52840

I would prefer to have the source so I can add a serial bootloader and update the NCP itself in the future.

[Edvin]

Hello,

That is true. nrfutil will probably by default use the serial (UART) interface between the programmer chip and the nRF52840. 

It looks like the hex file that is programmed to the nRF52840 by nrfutil is just a default NCP example from the nRF5 SDK. 

However, I have some good and some bad news. I set up a Thread DFU test, using 2x nRF52840 DKs. 

Normal DFU using nrfutil and "nrfutil dfu thread -f ..." works just fine.

Then I tried to flash the thread\ncp\ftd\uart example, and then the "nrfutil dfu thread ..." without the -f flag works as well.

However, when I tried the ncp\ftd\usb example, it doesn't work out of the box using nrfutil. It throws an error saying it can't reset the device, so it looks like you need to do some changes to nrfutil.

So the bad news are that you need to do some modifications and rebuild nrfutil. The good news is that you can use the default NCP example from the SDK.

If you can use this example for everything you need to do with the connected USB device, then you are almost there already. If you need to use another project, you need to add a USB bootloader that you can use to change between the NCP example and your custom project.

nrfutil's source code is available here:

https://github.com/NordicSemiconductor/pc-nrfutil 

Best regards,

Edvin

[Jay]

Thanks I did not realize the coap was done with spinel.