This document uses:
You may want to review the blog here for a more comprehensive overview of the DFU process. Performing a DFU on the nRF52805, nRF52810 or nRF52811 is somewhat simpler as it is only possible to DFU the application, due to the limited flash memory.
Generate the Keys
nrfutil keys display --key pk --format hex priv.pem
nrfutil keys display --key pk --format code priv.pem
nrfutil keys display --key pk --format code priv.pem --out_file dfu_public_key.c
Browse to the keys folder from step 1, select the dfu_public_key.c file and click Open. On the SES menu bar click Build → Build and Run and close SES when the process completes.
LEDs 1 and 2 on the DK will light. Use nRF Connect on your mobile device to see the DK is advertising as DfuTarg.
Creating a DFU Zip Package
Performing the DFU
The progress screen will appear. When the DFU is complete, DfuTarg will disconnect, the nRF52 will reboot and the beacon application will run. Note that LED1 on the DK is blinking, indicating that advertising is occurring (if the LED stops blinking, press the reset button to reset the timeout). Use nRF Connect on your mobile device to scan and find the beacon advertising.