.. zephyr:code-sample:: nrf_system_off
   :name: System Off
   :relevant-api: sys_poweroff subsys_pm_device

   Use deep sleep on Nordic platforms.

Overview

THIS REQUIRES AN NRF54L15DK, OR ADJUSTMENTS TO THE BIT DEFINES IN main.c

This sample can be used for basic power measurement and as an example of deep sleep on Nordic platforms and utilize the latch register to determine wakeup source. https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/gpio.html#ariaid-title15

It is overly verbose for educational purposes.

You can press switch 0-3 to see an LED blink the set number times and then go to sleep.

RAM Retention

This sample can also demonstrate RAM retention. By selecting CONFIG_APP_USE_RETAINED_MEM=y state related to number of boots, number of times system off was entered, and total uptime since initial power-on are retained in a checksummed data structure. RAM is configured to keep the containing section powered while in system-off mode.

Requirements

This application uses nRF54L15 DK board for the demo.

Sample Output

nRF54 core output

*** Booting Zephyr OS build v2.3.0-rc1-204-g5f2eb85f728d  ***
*** Using Zephyr OS v3.7.99-1f8f3dc29142 ***

nrf54l15dk system off demo
LATCH REGISTER FOR P0: 0
LATCH REGISTER FOR P1: 512
WAKEUP SRC: SW1
Retained data not supported
Entering system off; press any switch to restart
*** Booting nRF Connect SDK v2.9.0-7787b2649840 ***
*** Using Zephyr OS v3.7.99-1f8f3dc29142 ***

nrf54l15dk system off demo
LATCH REGISTER FOR P0: 0
LATCH REGISTER FOR P1: 256
WAKEUP SRC: SW2
Retained data not supported
Entering system off; press any switch to restart

Power Measurement