/**
* @brief Enters in Under-Drive STOP mode.
*
* @note This mode can be selected only when the Under-Drive is already active
*
* @note This mode is enabled only with STOP low power mode.
* In this mode, the 1.2V domain is preserved in reduced leakage mode. This
* mode is only available when the main regulator or the low power regulator
* is in low voltage mode
*
* @note If the Under-drive mode was enabled, it is automatically disabled after
* exiting Stop mode.
* When the voltage regulator operates in Under-drive mode, an additional
* startup delay is induced when waking up from Stop mode.
*
* @note In Stop mode, all I/O pins keep the same state as in Run mode.
*
* @note When exiting Stop mode by issuing an interrupt or a wakeup event,
* the HSI RC oscillator is selected as system clock.
*
* @note When the voltage regulator operates in low power mode, an additional
* startup delay is incurred when waking up from Stop mode.
* By keeping the internal regulator ON during Stop mode, the consumption
* is higher although the startup time is reduced.
*
* @param Regulator: specifies the regulator state in STOP mode.
* This parameter can be one of the following values:
* @arg PWR_MAINREGULATOR_UNDERDRIVE_ON: Main Regulator in under-drive mode
* and Flash memory in power-down when the device is in Stop under-drive mode
* @arg PWR_LOWPOWERREGULATOR_UNDERDRIVE_ON: Low Power Regulator in under-drive mode
* and Flash memory in power-down when the device is in Stop under-drive mode
* @param STOPEntry: specifies if STOP mode in entered with WFI or WFE instruction.
* This parameter can be one of the following values:
* @arg PWR_SLEEPENTRY_WFI: enter STOP mode with WFI instruction
* @arg PWR_SLEEPENTRY_WFE: enter STOP mode with WFE instruction
* @retval None
*/
HAL_StatusTypeDef HAL_PWREx_EnterUnderDriveSTOPMode(uint32_t Regulator, uint8_t STOPEntry)
{
uint32_t tempreg = 0;
uint32_t tickstart = 0;
/* Check the parameters */
assert_param(IS_PWR_REGULATOR_UNDERDRIVE(Regulator));
assert_param(IS_PWR_STOP_ENTRY(STOPEntry));
/* Enable Power ctrl clock */
__HAL_RCC_PWR_CLK_ENABLE();
/* Enable the Under-drive Mode ---------------------------------------------*/
/* Clear Under-drive flag */
__HAL_PWR_CLEAR_ODRUDR_FLAG();
/* Enable the Under-drive */
__HAL_PWR_UNDERDRIVE_ENABLE();
/* Get tick */
tickstart = HAL_GetTick();
/* Wait for UnderDrive mode is ready */
while(__HAL_PWR_GET_FLAG(PWR_FLAG_UDRDY))
{
if((HAL_GetTick() - tickstart ) > PWR_UDERDRIVE_TIMEOUT_VALUE)
{
return HAL_TIMEOUT;
}
}
/* Select the regulator state in STOP mode ---------------------------------*/
tempreg = PWR->CR1;
/* Clear PDDS, LPDS, MRLUDS and LPLUDS bits */
tempreg &= (uint32_t)~(PWR_CR1_PDDS | PWR_CR1_LPDS | PWR_CR1_LPUDS | PWR_CR1_MRUDS);
/* Set LPDS, MRLUDS and LPLUDS bits according to PWR_Regulator value */
tempreg |= Regulator;
/* Store the new value */
PWR->CR1 = tempreg;
/* Set SLEEPDEEP bit of Cortex System Control Register */
SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk;
/* Select STOP mode entry --------------------------------------------------*/
if(STOPEntry == PWR_SLEEPENTRY_WFI)
{
/* Request Wait For Interrupt */
__WFI();
}
else
{
/* Request Wait For Event */
__WFE();
}
/* Reset SLEEPDEEP bit of Cortex System Control Register */
SCB->SCR &= (uint32_t)~((uint32_t)SCB_SCR_SLEEPDEEP_Msk);
return HAL_OK;
}
/**
* @brief Enters in Under-Drive STOP mode.
*
* @note This mode is only available for STM32F42xxx/STM3243xxx devices.
*
* @note This mode can be selected only when the Under-Drive is already active
*
* @note In Stop mode, all I/O pins keep the same state as in Run mode.
* @note When exiting Stop mode by issuing an interrupt or a wakeup event,
* the HSI RC oscillator is selected as system clock.
* @note When the voltage regulator operates in low power mode, an additional
* startup delay is incurred when waking up from Stop mode.
* By keeping the internal regulator ON during Stop mode, the consumption
* is higher although the startup time is reduced.
*
* @param PWR_Regulator: specifies the regulator state in STOP mode.
* This parameter can be one of the following values:
* @arg PWR_MainRegulator_UnderDrive_ON: Main Regulator in under-drive mode
* and Flash memory in power-down when the device is in Stop under-drive mode
* @arg PWR_LowPowerRegulator_UnderDrive_ON: Low Power Regulator in under-drive mode
* and Flash memory in power-down when the device is in Stop under-drive mode
* @param PWR_STOPEntry: specifies if STOP mode in entered with WFI or WFE instruction.
* This parameter can be one of the following values:
* @arg PWR_STOPEntry_WFI: enter STOP mode with WFI instruction
* @arg PWR_STOPEntry_WFE: enter STOP mode with WFE instruction
* @retval None
*/
void PWR_EnterUnderDriveSTOPMode(uint32_t PWR_Regulator, uint8_t PWR_STOPEntry)
{
uint32_t tmpreg = 0;
/* Check the parameters */
assert_param(IS_PWR_REGULATOR_UNDERDRIVE(PWR_Regulator));
assert_param(IS_PWR_STOP_ENTRY(PWR_STOPEntry));
/* Select the regulator state in STOP mode ---------------------------------*/
tmpreg = PWR->CR;
/* Clear PDDS and LPDS bits */
tmpreg &= CR_DS_MASK;
/* Set LPDS, MRLUDS and LPLUDS bits according to PWR_Regulator value */
tmpreg |= PWR_Regulator;
/* Store the new value */
PWR->CR = tmpreg;
/* Set SLEEPDEEP bit of Cortex System Control Register */
SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk;
/* Select STOP mode entry --------------------------------------------------*/
if(PWR_STOPEntry == PWR_STOPEntry_WFI)
{
/* Request Wait For Interrupt */
__WFI();
}
else
{
/* Request Wait For Event */
__WFE();
}
/* Reset SLEEPDEEP bit of Cortex System Control Register */
SCB->SCR &= (uint32_t)~((uint32_t)SCB_SCR_SLEEPDEEP_Msk);
}
