how to change nrf54l15dk console from uart20 to uart21?

[casey shen]

hi,

I use nrf54l15dk with ncs-v3.1.0， the project is based sample "central_hids"；

The purpose is I want to change console uart from "pin1.04/pin1.05<uart20>" to "pin2.07/pin2.08<uart21>"；

If I change the overlay as below,and init <uart21> in main function;

It seems that the chip doesn't work;

If I change it back as default,It can work well with <uart20>

wish  for your reply,thank you;

&uart20 {
    status = "disabled";
};

&led2 {
    status = "disabled";
};

//&trace {
//    status = "okay";
//};

&pinctrl {
    uart21_default: uart21_default {
        group1 {
            psels = <NRF_PSEL(UART_TX, 2, 8)>;
        };
        group2 {
            psels = <NRF_PSEL(UART_RX, 2, 7)>;
            bias-pull-up;
        };
    };
    uart21_sleep: uart21_sleep {
        group1 {
            psels = <NRF_PSEL(UART_TX, 2, 8)>, <NRF_PSEL(UART_RX, 2, 7)>;
            low-power-enable;
        };
    };
};

&uart21 {
    status = "okay";
    current-speed = <115200>;
    pinctrl-0 = <&uart21_default>;
    pinctrl-1 = <&uart21_sleep>;
    pinctrl-names = "default", "sleep";
};



/ {
    chosen {
        zephyr,console = &uart21;
        zephyr,shell-uart = &uart21;
    };
};

//it's my init for uart21；
const struct device *uart = DEVICE_DT_GET(DT_NODELABEL(uart21));

int main(void){

    //it is I add in main function
	NRF_POWER->TASKS_CONSTLAT = 1;

	if (!device_is_ready(uart)){
    	return;
	}

[Vidar Berg]

Hello,

The driver will now request and release its request for constant latency mode automatically, but to use this feature you must add CONFIG_NRF_SYS_EVENT=y to your project configuration file (prj.conf). There is an assert to catch this problem at build time, but you need to have ASSERTs enabled for that (CONFIG_ASSERT=y).

Relevant commit: https://github.com/nrfconnect/sdk-zephyr/commit/20db3ee4cf31537296f92c68cea67cb7707c8f3d 

Best regards,

Vidar

[casey shen]

Hi,Vidar,

After I open the macro as you recommended,

My uart21 now can works some seconds,and then it will still let the nrf54l15dk death,the chips doesn't work ntill reset it;

Do you know how to solve this problem?

Thank you for your help.

//it's I add in prj.conf
CONFIG_NRFX_POWER=y
CONFIG_NRF_SYS_EVENT=y
CONFIG_ASSERT=y

//it's I think may take use,I dont know how to open and use those macro, still tring to use;
# CONFIG_UART_21_NRF_HW_ASYNC=y
# CONFIG_UART_21_NRF_HW_ASYNC_TIMER=22
# CONFIG_NRFX_TIMER22=y

[casey shen]

hi,if I use P1 gpio,I don't have all those problem;but my board is GPIO2;

[Vidar Berg]

casey shen said:

it just suddely don't work;stop suddenly,don't print error;

Unfortunately that does not say much. Here's what I see when I run your project here:

And here's the hex file from that build:

5483.merged.hex

Also, I see you have a duplicate private ticket going in parallel to this. Please avoid creating duplicate tickets.  

[casey shen]

thanks for helping,

this problem I decide to leave it in future to solve,

now I use transmit string to instead data buff. let mcu to parsing string data;

[odin huang]

Hi,

You must see it. P2 use UARTE00, 

The UARTE 20-23 instances currently seem to be restricted to use on P1.

devzone.nordicsemi.com/.../essential-pin-planning-guidelines-for-the-nrf54l-series

[casey shen]

Hi，odin,

Thank you for help;

P1 is general GPIO for UARTE20-23, and UARTE20 still have special function GPIO for P2.07/P2.08, it can see from datasheet .