Timed wakeup from deep sleep

[Iskailko]

I am using an nrf54l10 with the NRFconnect SDK. I would be interested in a solution to go into a low power state and wake up again after a specific time (multiple hours to days). Currently I am using sys_poweroff() but I only found solution to wake the system up via gpio inputs. Is there specific solution recommended for this kind of problem?

Thanks and regards,

Vito

[Iskailko]

I got the sample to work on my board. Unfortunately I see the same behavior. After going to sleep the board does not wake up again. I know that its asleep because I can wake it up again via GPIO (button press).  This is my output and then nothing happens.

*** Booting nRF Connect SDK v3.0.2-89ba1294ac9b ***<\r>
<\n>*** Using Zephyr OS v4.0.99-f791c49f492c ***<\r>
<\n><\r>
<\n>nrf54l15dk system off demo<\r>
<\n>Reset by debugger.<\r>
<\n>Retained data not supported<\r>
<\n>Entering system off; wait 2 seconds to restart

I had no development board at hand so I installed the sample on one of my custom boards. I had to adjust the proj.conf as I am using the internal 32 kHz Clock: 

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_500PPM=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC_CALIBRATION=y

CONFIG_CLOCK_CONTROL_NRF_CALIBRATION_LF_ALWAYS_ON=y

Could this be a reason for the sample to not work as intended?

[Einar Thorsrud]

Hi,

I see. Wakeup from system OFF is only possible using LFXO (with external 32.768 kHz crystal). This is described indirectly under LFCLK controller:

LFXO can run in System OFF mode. The other clock sources only run in System ON mode.

So you your options are to use system ON low power mode (the normal sleep mode where the CPU sleeps and you put other peripherals in low power states), use another wakeup source, or add a 32.768 kHz crystal to your custom board.

[Iskailko]

Thank you we added a 32.768 kHz crystal and it worked.