nrfutil pkg generate --debug-mode --application _build/ruuvi_firmware.hex --hw-version 3 --sd-req 0x91 --key-file ~/git/ruuvitag_fw/keys/ruuvi_open_private.pem ruuvi_firmware_dfu.zip
nrfutil pkg generate --application _build/nrf52832_xxaa.hex --application-version 1 --hw-version 0xB0 --sd-req 0xB7 --key-file ruuvi_open_private.pem ${BINNAME}_dfu_app.zip
nrfutil settings generate --family NRF52 --application _build/nrf52832_xxaa.hex --application-version 1 --bootloader-version 1 --bl-settings-version 1 settings.hex
mergehex -m ../../../../nRF5_SDK_15.3.0_59ac345/components/softdevice/s132/hex/s132_nrf52_6.1.1_softdevice.hex $BOOTLOADER settings.hex -o sbc.hex
mergehex -m sbc.hex _build/nrf52832_xxaa.hex -o packet.hex
nrfjprog --eraseall
nrfjprog --program packet.hex
nrfjprog --reset
nrfjprog -f nrf52 --rbp ALL
nrfjprog --recover
to use the programming interface again. This completely erases the tag.