Suspend to RAM
Overview
This sample is a minimum application to demonstrate basic power management behavior in a basic blinking LED set up using the GPIO API in low power context + ADC measurements and entropy. SPI loopback is also available but not yet implemented for Suspend To RAM PM mode.
Requirements
The board should support enabling PM. For a STM32 based target, it means that
it should support a clock source alternative to Cortex Systick that can be used
in core sleep states, as LPTIM (st,stm32-lptim).
The board shall have an RTC to use it during the standby mode as a replacement
for LPTIM (which is disabled). The board shall also have RAM retention to be
able to restore context after standby.
Building and Running
Build and flash Blinky as follows, changing stm32wba55cg for your board:
west build -b stm32wba55cg samples/boards/st/power_mgmt/suspend_to_ram
west flash
After flashing, the LED starts to blink.
PM configurations
By default, CONFIG_PM_DEVICE and CONFIG_PM_DEVICE_RUNTIME
are enabled.