No TX activity for uart1 configuration on modified echo_bot example with nRF Connect SDK v2.1.0

RE: No TX activity for uart1 configuration on modified echo_bot example with nRF Connect SDK v2.1.0

Vidar Berg — Fri, 28 Jul 2023 12:17:38 GMT

Please submit your question in a new ticket. And remember to include details about your setup. E.g. SDK version, what serial client you use, etc.

RE: No TX activity for uart1 configuration on modified echo_bot example with nRF Connect SDK v2.1.0

Aayushi Kanojiya — Fri, 28 Jul 2023 12:12:26 GMT

I am running default code of echo_n=bot on nrf52840-dk board but it is not showing any output by giving input on console

RE: No TX activity for uart1 configuration on modified echo_bot example with nRF Connect SDK v2.1.0

Vidar Berg — Wed, 28 Sep 2022 13:34:47 GMT

Thanks for making me aware of this issue and sorry for the confusion caused by it. I will follow up internally to get the docs fixed. This is clearly a documentation error as the suggested overlay does not match the configuration used in our board files which have 2 groups for UART as you can see here link.

With the overlay given in the documentation, only group1 with the RX pin will be overridden. The TX pin in group2 will remain unchanged.

Grouping is needed when you need to apply a specific property for some of the pins. Like for UART0 where we want to enable pull-up on UART RX and CTS, but not on the TX and RTS line.

RE: No TX activity for uart1 configuration on modified echo_bot example with nRF Connect SDK v2.1.0

jeraymond — Tue, 27 Sep 2022 17:59:42 GMT

That fixed the problem, thanks! This looks to be a bug in the documentation I pulled the example overlay from (here). What's the best way to get the docs fixed?

What does group1 and group2 represent in the overlay; could you point me to the docs on the uart configs?

RE: No TX activity for uart1 configuration on modified echo_bot example with nRF Connect SDK v2.1.0

Vidar Berg — Tue, 27 Sep 2022 15:31:26 GMT

Hello,

It looks like you are missing the second group for the default state in your overlay. Please try this:

&pinctrl {
	uart1_default: uart1_default {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 14)>;
		};
        group2 {
            psels = <NRF_PSEL(UART_RX, 0, 16)>;
        };

	};
	/* required if CONFIG_PM_DEVICE=y */
	uart1_sleep: uart1_sleep {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 14)>,
					<NRF_PSEL(UART_RX, 0, 16)>;
			low-power-enable;
		};
	};
};

You can also route 'zephyr_shell_uart' to uart1 if you override "chosen" like this:

/ {
    chosen {
        zephyr,console = &uart1;
		zephyr,shell-uart = &uart1;
    };
};

Hope this helps.

Best regards,

Vidar