Using pin P0.00 and P0.01 as RX TX of UART

[pulkit]

I want to use P0.00 and P0.01 as UART pins.
I have shorted the SB3 and SB4, and opened the SB1 and SB2 for using the pin as GPIO.

If I am enabling the "CONFIG_BOOTLOADER_MCUBOOT=y", I am not able to see the log on UART. If I disable this config I can see the logs. Can you please help so that I can use the UART along with the "CONFIG_BOOTLOADER_MCUBOOT=y".

Also used config for using P0.00 and P0.01 as GPIO

CONFIG_GPIO=y
CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y
CONFIG_CLOCK_CONTROL_NRF_K32SRC_500PPM=y
CONFIG_CLOCK_CONTROL_NRF_K32SRC_SYNTH=y

 

[Menon]

Hello,

Could you please tell me which SDK version and Nordic chip or DK you are using here? How are you configuring the UART logging when enabling the Bootloader? Have you tested it using any other pins? Do the UART logs work in that case?

Kind regards,

Abhijith

[pulkit]

I am using SDK version v2.6.1 with nrf52833. I have tested with the other pins for RX TX and its working but when I configured RX TX with P0.00 and P0.01, I am not able to see any logs.

uart0_default: uart0_default {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 1)>,
				<NRF_PSEL(UART_RTS, 0, 5)>;
		};
		group2 {
			psels = <NRF_PSEL(UART_RX, 0, 0)>,
				<NRF_PSEL(UART_CTS, 0, 7)>;
			bias-pull-up;
		};
	};

	uart0_sleep: uart0_sleep {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 1)>,
				<NRF_PSEL(UART_RX, 0, 0)>,
				<NRF_PSEL(UART_RTS, 0, 5)>,
				<NRF_PSEL(UART_CTS, 0, 7)>;
			low-power-enable;
		};
	};

[Menon]

Hello,

Your UART configuration in DTS looks fine to me. I am not sure if there is any conflict with MCUboot when using these pins as UART.

Try including the configurations below inside the mcuboot.config file (child_image\mcuboot.conf). See if this makes any difference. If not, I recommend sharing a minimal project so I can review it to determine whether there is any conflict.

# Disable UART console in MCUboot
CONFIG_UART_CONSOLE=n
CONFIG_USE_SEGGER_RTT=n

Best regards,
Abhijith