RE: Floating UART RX Pin causes higher power consumption (pin 23)

Håkon Alseth — Wed, 03 Jan 2024 09:11:35 GMT

Hi,

[quote user="thijsfranssen"]Best wishes for 2024![/quote]

Thank you, and like-wise to you as well!

[quote user="thijsfranssen"]I just noticed it could also be caused by a faulty GPIO power supply. The FTDI cable has a higher voltage on the TX line compared to the VDD_GPIO line. I will further look into this coming week. [/quote]

This will trigger the internal ESD protection diodes if it exceeds VDD_GPIO + 0.3V, and thus leak a bit of current.

For debugging purposes; you could try to add a series-resistor, in the 1k area, to see if this helps wrt. the higher sleep current.

Kind regards,

Håkon

RE: Floating UART RX Pin causes higher power consumption (pin 23)

thijsfranssen — Tue, 02 Jan 2024 16:29:39 GMT

I just noticed it could also be caused by a faulty GPIO power supply. The FTDI cable has a higher voltage on the TX line compared to the VDD_GPIO line. I will further look into this coming week.

RE: Floating UART RX Pin causes higher power consumption (pin 23)

thijsfranssen — Tue, 02 Jan 2024 14:56:33 GMT

Hi,

Best wishes for 2024!

It doesn't seem to make a difference. I changed it in the overlay file and also tried to change it in the root file. Even when the pins are not configured at all I see the same power consumption.

The devicetree files are based on the nrf9160dk files. I removed all the stuff I don't need such as the uart2 which uses the same pins as I want to use for uart0

Could you maybe check my devicetree files?

This is my pinctrl.dtsi file:

/*
 * Copyright (c) 2022 Nordic Semiconductor
 * SPDX-License-Identifier: Apache-2.0
 */

&pinctrl {
	uart0_default: uart0_default {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 24)>;
		};
		group2 {
			psels = <NRF_PSEL(UART_RX, 0, 23)>;
			bias-pull-up;
		};
	};

	uart0_sleep: uart0_sleep {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 24)>,
				<NRF_PSEL(UART_RX, 0, 23)>;
			low-power-enable;
		};
	};

	i2c2_default: i2c2_default {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 0, 30)>,
				<NRF_PSEL(TWIM_SCL, 0, 31)>;
		};
	};

	i2c2_sleep: i2c2_sleep {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 0, 30)>,
				<NRF_PSEL(TWIM_SCL, 0, 31)>;
			low-power-enable;
		};
	};

};

This is the common.dtsi file:

/*
 * Copyright (c) 2018-2020 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#include "nrf9160dk_nrf9160_common-pinctrl.dtsi"
#include <zephyr/dt-bindings/input/input-event-codes.h>

/ {
	model = "Nordic nRF9160 DK NRF9160";
	compatible = "nordic,nrf9160-dk-nrf9160";

	chosen {
		zephyr,console = &uart0;
		zephyr,shell-uart = &uart0;
		zephyr,uart-mcumgr = &uart0;
	};

	leds {
		compatible = "gpio-leds";
		led0: led_0 {
			gpios = <&gpio0 2 0>;
			label = "Green LED 1";
		};
		led1: led_1 {
			gpios = <&gpio0 3 0>;
			label = "Green LED 2";
		};
		led2: led_2 {
			gpios = <&gpio0 4 0>;
			label = "Green LED 3";
		};
		led3: led_3 {
			gpios = <&gpio0 5 0>;
			label = "Green LED 4";
		};
	};

	pwmleds {
		compatible = "pwm-leds";
		pwm_led0: pwm_led_0 {
			pwms = <&pwm0 0 PWM_MSEC(20) PWM_POLARITY_NORMAL>;
		};
	};

	buttons {

		compatible = "gpio-keys";
		button0: button_0 {
			gpios = <&gpio0 6 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
			label = "Push button 1";
			zephyr,code = <INPUT_KEY_0>;
		};
		button1: button_1 {
			gpios = <&gpio0 7 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
			label = "Push button 2";
			zephyr,code = <INPUT_KEY_1>;
		};
		button2: button_2 {
			gpios = <&gpio0 8 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
			label = "Switch 1";
			zephyr,code = <INPUT_KEY_2>;
		};
		button3: button_3 {
			gpios = <&gpio0 9 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
			label = "Switch 2";
			zephyr,code = <INPUT_KEY_3>;
		};
	};



	/* These aliases are provided for compatibility with samples */
	aliases {
		led0 = &led0;
		pwm-led0 = &pwm_led0;
		sw0 = &button0;
		sw1 = &button1;
		bootloader-led0 = &led0;
		mcuboot-button0 = &button0;
		mcuboot-led0 = &led0;
		watchdog0 = &wdt0;
	};
};

&adc {
	status = "okay";
};

&gpiote {
	status = "okay";
};

&gpio0 {
	status = "okay";
};

&uart0 {
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart0_default>;
	pinctrl-1 = <&uart0_sleep>;
	pinctrl-names = "default", "sleep";
};


&i2c2 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	pinctrl-0 = <&i2c2_default>;
	pinctrl-1 = <&i2c2_sleep>;
	pinctrl-names = "default", "sleep";
};


&flash0 {

	partitions {
		compatible = "fixed-partitions";
		#address-cells = <1>;
		#size-cells = <1>;

		boot_partition: partition@0 {
			label = "mcuboot";
			reg = <0x00000000 0x10000>;
		};
		slot0_partition: partition@10000 {
			label = "image-0";
		};
		slot0_ns_partition: partition@50000 {
			label = "image-0-nonsecure";
		};
		slot1_partition: partition@80000 {
			label = "image-1";
		};
		slot1_ns_partition: partition@c0000 {
			label = "image-1-nonsecure";
		};
		/* 0xf0000 to 0xf7fff reserved for TF-M partitions */
		storage_partition: partition@f8000 {
			label = "storage";
			reg = <0x000f8000 0x00008000>;
		};
	};
};

/ {

	reserved-memory {
		#address-cells = <1>;
		#size-cells = <1>;
		ranges;

		sram0_s: image_s@20000000 {
			/* Secure image memory */
		};

		sram0_modem: image_modem@20016000 {
			/* Modem (shared) memory */
		};

		sram0_ns: image_ns@20020000 {
			/* Non-Secure image memory */
		};
	};
};

/* Include partition configuration file */
#include "nrf9160dk_nrf9160_partition_conf.dtsi"

This is the project dts file:

/*
 * Copyright (c) 2018-2020 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */

/dts-v1/;
#include <nordic/nrf9160ns_sica.dtsi>
#include "nrf9160dk_nrf9160_common.dtsi"

/ {
	chosen {
		zephyr,flash = &flash0;
		zephyr,sram = &sram0_ns;
		zephyr,code-partition = &slot0_ns_partition;
	};
};

/* Disable UART1, because it is used by default in TF-M */
&uart1 {
	status = "disabled";
};

and this is the overlay file:

/*
 * Copyright (c) 2023 Golioth, Inc.
 *
 * SPDX-License-Identifier: Apache-2.0
 */

/ {
	aliases {
		golioth-led = &led0;
        sw5 = &switch0;		
	};

	switches {
		compatible = "gpio-keys";

		switch0: switch_0 {
			gpios = <&gpio0 19 0>;
			label = "5V Switch";
		};
	};		
};


&i2c2 {  
	tfluna: tfluna@10{
		compatible = "i2c-device";
		reg = < 0x10 >;
		label = "tfluna";
	};
};	

&adc {
	status = "disabled";
};

RE: Floating UART RX Pin causes higher power consumption (pin 23)

Håkon Alseth — Fri, 29 Dec 2023 14:33:28 GMT

Hi,

Could you try to enable the internal pull on the RXD pin?

Here's how you set that in DT: https://github.com/nrfconnect/sdk-zephyr/blob/v3.4.99-ncs1-1-rc1/boards/arm/nrf9160dk_nrf9160/nrf9160dk_nrf9160_common-pinctrl.dtsi#L15

Kind regards,

Håkon