Wakeup Pins Configuration Functions; Low Power Modes Configuration Functions - ST STM32F31xx User Manual

Power control (PWR)
17.2.3

WakeUp pins configuration functions


WakeUp pins are used to wakeup the system from Standby mode. These pins are
forced in input pull down configuration and are active on rising edges.

There are three WakeUp pins: WakeUp Pin 1 on PA.00, WakeUp Pin 2 on PC.13 and
WakeUp Pin 3 on PE.06.

PWR_WakeUpPinCmd()
17.2.4

Low Power modes configuration functions

The devices feature three low-power modes:

Sleep mode: Cortex-M4 core stopped, peripherals kept running.

Stop mode: all clocks are stopped, regulator running, regulator in low power mode

Standby mode: VCORE domain powered off
Sleep mode

Entry:


Exit:

Stop mode
In Stop mode, all clocks in the VCORE domain are stopped, the PLL, the HSI, and the
HSE RC oscillators are disabled. Internal SRAM and register contents are preserved. The
voltage regulator can be configured either in normal or low-power mode.

Entry:


Exit:

Standby mode
The Standby mode allows to achieve the lowest power consumption. It is based on the
Cortex-M4 deepsleep mode, with the voltage regulator disabled. The VCORE domain is
consequently powered off. The PLL, the HSI, and the HSE oscillator are also switched off.
SRAM and register contents are lost except for the Backup domain (RTC registers, RTC
backup registers and Standby circuitry).
The voltage regulator is OFF.

Entry:


Exit:
302/584
The Sleep mode is entered by executing the WFE() or WFI() instructions.
Any peripheral interrupt acknowledged by the nested vectored interrupt controller
(NVIC) can wake up the device from Sleep mode.
The Stop mode is entered using the
PWR_EnterSTOPMode(PWR_Regulator_LowPower,) function with regulator in
LowPower or with Regulator ON.
Any EXTI Line (Internal or External) configured in Interrupt/Event mode or any
internal IPs (I2C or UASRT) wakeup event.
The Standby mode is entered using the PWR_EnterSTANDBYMode() function.
DocID023800 Rev 1
UM1581