Adding ble dfu for nrf52840 dongle

[Desmond G]

Hi, I am currently working on implement ble dfu on the nrf52840 dongle. I tried following this https://devzone.nordicsemi.com/guides/nrf-connect-sdk-guides/b/software/posts/ncs-dfu and it works on the nrf52dk. However, it didnt work on the dongle. The only difference in changes i have made between nrf52dk and the dongle is that i use mcumgr to flash the dongle and west flash for the dk. I tried smp_server example and used the usb cdc overlay. Whenever i tried to use the mcumgr echo command, nothing responded but i could still upload the bin file. Did i somehow set it wrongly? 

I am currently developing on NCS v1.5.1.

[Einar Thorsrud]

Hi,

The nRF52840 Dongle ships with a nRF5 SDK based USB bootloader, and that complicates things quite a bit, and the guide about DFU in nRF Connect SDK does not cover it. Why do you want Bluetooth DFU on a USB dongle in the first place? If you are using it as a development kit and want to develop Bluetooth DFU for use on a custom board in the future then I suggest using a DK instead, as that way what you do are transferable to what you would use in a custom board (which does not have the USB bootloader).