The primary debug interface on the nRF9160 DK is the Segger OB debugger available through the Universal Serial Bus (USB) port. However, if other than USB supply is used on the Development Kit (DK), this functionality will be disabled.
The Debug in connectors P18 (nRF9160) and P23 (nRF52840) make it possible to connect external debuggers for debugging when the interface USB cable is not connected or if the DK is in IF MCU DISCONNECT mode.
To utilize the SW trace feature on nRF9160, a footprint for a 20-pin connector is available (P25). If trace functionality is required, a 2×10 pin 1.27 mm pitch surface mount connector can be mounted. nRF9160 General-Purpose Input/Output (GPIO)s used for the trace interface will not be available for application firmware use during trace.
| GPIO | Trace |
|---|---|
| P0.21 | TRACECLK |
| P0.22 | TRACEDATA[0] |
| P0.23 | TRACEDATA[1] |
| P0.24 | TRACEDATA[2] |
| P0.25 | TRACEDATA[3] |