sleep mode of nRF52840 in NCS

[peter_liu]

I'm working on NCS 1.6.1 for both nRF52840 and nRF9160.

I'm trying to put my devices into sleep mode so i reviewed some related tickets and found following ways.

NRF_REGULATORS->SYSTEMOFF=1     //this seems only to be supported in nrf9160

and

pm_power_state_force(struck pm_state_info info)

i wonder what is the better way to go with? and what is the difference between these two? 

and are there any samples showing how to  manipulate sleep mode? 

[Simonr]

Hi

Please check out the Power Management subsystem in the Zephyr RTOS which is what the nRFConnect SDK (NCS) applications use for power management. The list of available power states is defined by pm_state. The recommended way to go to sleep is neither of these, as the PM_STATE_STANDBY or PM_STATE_RUNTIME_IDLE are better suited to put devices into sleep modes, instead of "forcing" them to sleep modes.

Best regards,

Simon

[peter_liu]

actually, I just wanted to force it to sleep mode for some HW test for now.

so, is the following correct way ?

info.state=PM_STATE_RUNTIME_IDLE;
pm_power_state_force( info);

[Simonr]

Hi

Please check out the nRF5x system OFF sample project in Zephyr which uses pm_power_state_force correctly to force an nRF5x device to system OFF. It can be found in ...\<NCS_FOLDER>\v1.7.0\zephyr\samples\boards\nrf\system_off\src\main.c

Best regards,

Simon

[peter_liu]

thanks, it's very helpful.