For boards with a standard 10-pin Serial Wire Debug (SWD) connector or a connector that supports a standard 10-pin flat cable, connection to P19 is recommended.
Connect the boards as shown in the following figure.
When the interface MCU detects the voltage of the external board on pin 1 (SWD0_VTG) of P19, it programs or debugs the target chip on the external board instead of the onboard nRF9161 System in Package (SiP).
The following figure and table show the P19 pinout.
Pin number | Signal | Description |
---|---|---|
1 | SELECT | Voltage supply from the external target, used as a select pin for the interface MCU to enable this port |
2 | SWDIO | SWD Data Input/Output |
3 | GND | Ground |
4 | SWDCLK | Serial wire clock line |
5 | GND | Ground |
6 | SW0 | Serial Wire Output (SWO) line is not used for programming and debugging over SWD |
7 | N.C. | Not used |
8 | N.C. | Not used |
9 | N.C. | Not used |
10 | RESET | Reset line |
If you do not have a separate power supply on the external board connected to the Debug out connector P19, the external board can be powered from the onboard DK regulator as follows: