RE: [nRF54L15 DK][Zephyr] How to implement deep sleep + interrupt-driven wakeup?

Elfving — Wed, 03 Sep 2025 10:54:01 GMT

Hi Vishnu,

When it comes to power off, I believe that might be a bit different on the 54L15. We have a bit about that here, and here for instance, though this quick sample mentioned by a colleague of mine might be more helpful.

And regarding having a pin wake-up, have a look at this other quick example I made for a customer earlier, that I think should also work for the nRF54L15 as well. You might have to add target_include_directories(app PRIVATE hal) to cmakelists to run it.

#include <stdio.h>
#include <zephyr/kernel.h>
#include <zephyr/drivers/gpio.h>


#include <hal/nrf_gpio.h>
#include <hal/nrf_power.h>
#include <hal/nrf_regulators.h>

/* 1000 msec = 1 sec */
#define SLEEP_TIME_MS   1000

/* The devicetree node identifier for the "led0" alias. */
#define LED0_NODE DT_ALIAS(led0)

/* The devicetree node identifier for the "sw0" alias (button0). */
#define SW0_NODE DT_ALIAS(sw0)

/*
 * A build error on this line means your board is unsupported.
 * See the sample documentation for information on how to fix this.
 */
static const struct gpio_dt_spec led = GPIO_DT_SPEC_GET(LED0_NODE, gpios);
static const struct gpio_dt_spec button = GPIO_DT_SPEC_GET(SW0_NODE, gpios);

int main(void)
{
	int ret;
	int iterate=0;
	int naptime = 6;
	bool led_state = true;
	printk("Count down to System OFF mode: T-%d blinks\n", naptime/2);

	if (!gpio_is_ready_dt(&led)) {
		return 0;
	}

	if (!gpio_is_ready_dt(&button)) {
		printk("Error: button device %s is not ready\n", button.port->name);
		return 0;
	}

	ret = gpio_pin_configure_dt(&led, GPIO_OUTPUT_ACTIVE);
	if (ret < 0) {
		return 0;
	}

	ret = gpio_pin_configure_dt(&button, GPIO_INPUT);
	if (ret < 0) {
		printk("Error %d: failed to configure %s pin %d\n",
		       ret, button.port->name, button.pin);
		return 0;
	}

	/* Configure the button pin for wake-up on low signal (button press) */
	nrf_gpio_cfg_sense_set(button.pin, NRF_GPIO_PIN_SENSE_LOW);

	while (iterate < naptime) {
		ret = gpio_pin_toggle_dt(&led);
		if (ret < 0) {
			return 0;
		}
		iterate++;

		led_state = !led_state;
		printf("LED state: %s\n", led_state ? "ON" : "OFF");
		k_msleep(SLEEP_TIME_MS);
	}

	printk("Entering sleep mode...\n");
	/* Enter sleep mode */
	nrf_regulators_system_off(NRF_REGULATORS);

	return 0;
}

[quote user=""]wakeup-source[/quote]

I am not that familiar with the wakeup-source property, but I do not think it does much by itself.

Regards,

Elfving