Getting logging output with nRF5340 DK

When connected to a computer, the nRF5340 DK emulates virtual COM ports. The number of COM ports depends on the DK version you are using.

nRF5340 DK v2.0.0 COM ports

When connected to a computer, the nRF5340 DK v2.0.0 emulates two virtual COM ports. In the default configuration, they are set up as follows:

  • The first COM port outputs the log from the network core (if available).

  • The second COM port outputs the log from the application core.

nRF5340 DK v1.0.0 COM ports

When connected to a computer, the nRF5340 DK v1.0.0 emulates three virtual COM ports. In the default configuration, they are set up as follows:

  • The first COM port outputs the log from the network core (if available).

  • The second (middle) COM port is routed to the P24 connector of the nRF5340 DK.

  • The third (last) COM port outputs the log from the application core.

To use the middle COM port in the nRF5340 DK v1.0.0, complete the following steps:

  1. Map RX, TX, CTS and RTS pins to four different pins on the development kit, using, for example, devicetree overlays. See the following example, using the nordic,nrf-uarte bindings.

    &pinctrl {
   uart0_default_alt: uart0_default_alt {
      group1 {
         psels = <NRF_PSEL(UART_TX, 0, 20)>,
                 <NRF_PSEL(UART_RX, 0, 21)>,
                 <NRF_PSEL(UART_RTS, 0, 18)>,
                 <NRF_PSEL(UART_CTS, 0, 16)>;
      };
   };

   uart0_sleep_alt: uart0_sleep_alt {
      group1 {
         psels = <NRF_PSEL(UART_TX, 0, 20)>,
                 <NRF_PSEL(UART_RX, 0, 21)>,
                 <NRF_PSEL(UART_RTS, 0, 18)>,
                 <NRF_PSEL(UART_CTS, 0, 16)>;
         low-power-enable;
      };
   };
};

&uart0 {
   status = "okay";
   compatible = "nordic,nrf-uarte";
   current-speed = <115200>;
   pinctrl-0 = <&uart0_default_alt>;
   pinctrl-1 = <&uart0_sleep_alt>;
   pinctrl-names = "default", "sleep";
};

  2. Wire the previously mapped pins to TxD, RxD, CTS, and RTS on the P24 connector.