nrfutil dfu ble for custom boards

[TS Gowtham]

Hi,
I'm trying to implement DFU over BLE using nrfutil in a product. The product(will refer to as peripheral from this point onwards) also has a dongle(supports flow control). Both use a nRF52832 and both are custom boards i.e. they do not share the pinout with the nRF52 DK. Both of them have an application and bootloader based on SDK14.2.

I have seen many conflicting posts on devzone as to what version of the SDK, SD API version and nrfutil works.So these are my questions

-> Which version on SD API works with DFU over BLE using nrfutil?
-> Which version of nrfutil should I use?
-> Which version of the nRF5 SDK should I use? ( I will need to compile the connectivity firmware).
-> Is there any limitations on which SD API version the target peripheral can use?

The dongle, which I'm using as an intermediary between the PC and peripheral, has a Serial bootloader(based on SDK 14.2). So, I plan on using serial DFU to get the connectivity firmware to the dongle. I do not mind using any version of the SDK, SD API or nrfutil for the DFU. Please provide some answer for the above questions and suggest the best method for this problem.

Thanks,
Gowtham

[Vidar Berg]

Hi,

-> Which version on SD API works with DFU over BLE using nrfutil?

The current version of nrfutil uses pc-ble-driver-py v.11.4 which is a python wrapper for pc-ble-driver v.2.3.2. Instructions to build connectivity FW for these releases can be found here:  https://github.com/NordicSemiconductor/pc-ble-driver/blob/2d97262fa9940cb815778f01af9d05093558a72c/Installation.md#compiling-the-connectivity-hex-files 

Which version of nrfutil should I use?

 You can use the latest if you are using Secure DFU (v5.1.0 at the time of writing)

Which version of the nRF5 SDK should I use? ( I will need to compile the connectivity firmware).

 SDK 12. Installation guide doesn't specify the minor version number, but I would expect v.12.3.0 to work.

Is there any limitations on which SD API version the target peripheral can use?

 The connectivity FW  must be compiled for Softdevice version 3 API (ie s132 v3)

The dongle, which I'm using as an intermediary between the PC and peripheral, has a Serial bootloader(based on SDK 14.2). So, I plan on using serial DFU to get the connectivity firmware to the dongle.

 nrfutil BLE DFU will only work with a connectivity board programmed with the connectivity FW. But you can do serial DFU with nrfutil to program the connectivity FW.  

Regards,

Vidar