Connecting custom boards for programming
After you created custom board files, you need to connect your custom board to a debug probe for programming.
Hardware requirements
To connect a custom board for programming, you need the following hardware:
A debug probe supporting Serial Wire Debug (SWD), such as:
A Development Kit (DK) from Nordic Semiconductor (all include an onboard debug probe)
Dedicated debug adapter (like SEGGER J-Link)
Connecting wires
USB cable for the DK or the debug adapter
Required connections
You have to connect the following pins between your custom board and the debug probe:
Essential connections:
SWDCLK (Clock)
SWDIO (Data)
GND (Ground)
VTref (Target Reference Voltage)
Optional connections:
VDD - For powering the board from debug probe. If the custom board is not powered from VDD, it must be powered externally.
RESET - For resetting the board. If the custom board does not have a reset pin, you can use the reset pin on the debug probe.
Connecting the debug probe
The following steps describe how to connect your custom board to a debug probe.
Development Kits from Nordic Semiconductor include an onboard debug probe that supports the J-Link interface.
To connect your custom board to this onboard debug probe, complete the following steps:
Locate the SWD debug output header pins on your DK. Check the DK user guide on Nordic Semiconductor TechDocs for the exact location of these pins. For example, for the nRF52840 DK, read the Debug output page.
Connect the required pins to your custom board.
Connect the DK to your PC using the USB cable.
Install required J-Link drivers if not already present.
If you do not have a Development Kit, use a dedicated debug adapter:
Connect a compatible debug probe (like SEGGER J-Link) to your custom board. See the debug probe documentation for the exact pinout.
Install the appropriate debug interface drivers.
Connect the debug probe to your PC using the USB cable.
Note
The nRF Connect SDK supports various debug interfaces like J-Link and CMSIS-DAP, provided you have the proper drivers installed.
Programming custom boards
After you connected the custom board, you can program your application to the board using either the standard programming instructions or the Programmer app from nRF Connect for Desktop.