How to configure the Second UART port in the nRF52840 DK?

[Teja_K]

Hello,

Currently, I am working on the nRF 52840 DK and the UART port named uart0 is connected to the on board debugger, Where do i find the pins for the UART1 ? I could not able to figure it out. Please let me know how can we do this?

[SwRa]

HI Teja,

The default pin settings can be found in the DTS file.. It

Regards,

Swathy

[Teja_K]

Hi SwRa,

Here is my project configuration

When, I looked at the Device tree DTS file of nrf52840, the uart1 is set to arduino_serial

arduino_serial: &uart1 {

    current-speed = <115200>;

    pinctrl-0 = <&uart1_default>;

    pinctrl-1 = <&uart1_sleep>;

    pinctrl-names = "default", "sleep";

};

And the pin configuration is as follows

    uart1_default: uart1_default {

        group1 {

            psels = <NRF_PSEL(UART_RX, 1, 1)>;

            bias-pull-up;

        };

        group2 {

            psels = <NRF_PSEL(UART_TX, 1, 2)>;

        };

    };

The pins for UART1 is set to

           RX -  P1.01

           TX  - P1.02

In case if i want to enable RTS and CTS, which pins should i configure?

For my board, I created a device overlay file and want to enable UART1 in the overlay file. The following lines has been added.

/ {

    my_uart: &uart1 {

        compatible = "nordic,nrf-uarte";

        status = "okay";

        current-speed = <115200>;

        pinctrl-0 = <&uart1_default>;

        pinctrl-1 = <&uart1_sleep>;

        pinctrl-names = "default", "sleep";

    };

};

After all the settings, when i build the project, the build fails with following error

nrf52840dk_nrf52840.overlay:14 (column 14): parse error: expected node or property name

Do i just need to add the same settings that arduino_serial has in the overlay to configure it? Could you please suggest me how to configure this correctly?

Thanks & Regards

Teja