Deep Sleep mode in nRF54l15

[Nedaa_H_Ahmed]

Hello, 
I am using nRF Connect SDK v2.9.0. While working on the nRF52840 board, I used sys_poweroff() to put the board in deep sleep mode. But before calling it, I called

nrf_power_rampower_mask_on(NRF_POWER, 0, NRF_POWER_RAMPOWER_S0POWER_MASK);

nrf_power_rampower_mask_on(NRF_POWER, 1, NRF_POWER_RAMPOWER_S1POWER_MASK);

if I wanted to keep the RAM content in Deep Sleep and I called 

nrf_power_rampower_mask_off(NRF_POWER, 0, NRF_POWER_RAMPOWER_S0POWER_MASK);

nrf_power_rampower_mask_off(NRF_POWER, 1, NRF_POWER_RAMPOWER_S1POWER_MASK);

if I want to not keep the RAM content in Deep Sleep.

Now, I want to do migration and use the board nRF54L15 rather than nRF52840. When I replaced the board and tried to build the code, I got errors as these functions are undefined for the board nRF54L15.

Also, I got errors in 

uint32_t reset_reason = nrf_power_resetreas_get(NRF_POWER);

 nrf_power_resetreas_clear(NRF_POWER, reset_reason);

if (reset_reason & NRF_POWER_RESETREAS_RESETPIN_MASK)

{

   *penu_wakeup_reason = WAKEUP_FROM_EXT_PIN_RESET;

}

As, the functions nrf_power_resetreas_get, nrf_power_resetreas_clear, and NRF_POWER_RESETREAS_RESETPIN_MASK macro are not defined for the nRF54L15 board while they were working with the nRF52840 board

[Nedaa_H_Ahmed]

Yes, I mean system ON idle mode. Does that mean if I need to implement a function that enters the system in this mode, I should call k_sleep for all threads?

[Einar Thorsrud]

Hi,

Yes. As long as some threads have work to do (i.e. is not sleeping), the idle thread will not run. This is the same as for any other RTOS. So if you for insance want to wait/sleep, use k_sleep, as that will allow systme on sleep. If you instead with with for instance a loop (i.e. "busy wait"), the idle thread will not run, and the current consuption will be high. I recommend you go throught the nRF Connect fundamentals and intermediate courses (particularily Lesson 1 – Zephyr RTOS: Beyond the basics of the intemetiade course) to learn about this.