nrfutil DFU BLE and connectivity firmware

Hey Guys,

I noticed when I use nrfutil DFU BLE command on the nRF52 DK the nrfutil program a "connectivity firmware" before the perform the DFU BLE to a Target device.

The issue I am facing is I am using a custom hardware with a different pinout that nRF52 DK and with no J-Link OB like the nRF5X DK boards. Making incompatible it with the "connectivity firmware"

Are there any documentation to use nrfutil DFU BLE using a custom hardware with no J-Link OB chip? or where can I find an using that firmware (I dont know the correct name) to edit the board.h and make it compatible with my hardware and be able to make BLE DFU from a window PC

Regards, Marco