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STM32F415 - RTC Wake up while EXTI set

Dams
Associate II

Hello,

I have a problem by using 2 wake up sources: RTC wake up and EXTI (on PWR_WAKEUP_PIN1).

Both of them works but a problem occurs when EXTI line (on PA0) is high when RTC event occurs. It make the CPU frozzen and nothing happen.

I found a clue on "STM32F40x and STM32F41x Errata sheet" (2.1.5) but I shall catch only EXTI on rising edge (not when pin high).

Here is my code:

//----------------------------------------------------------------------

//HAL_PWR_DisableWakeUpPin(PWR_WAKEUP_PIN1);

__HAL_PWR_PVD_EXTI_DISABLE_EVENT();

__HAL_PWR_PVD_EXTI_DISABLE_IT();

__HAL_PWR_PVD_EXTI_DISABLE_RISING_EDGE();

__HAL_PWR_PVD_EXTI_DISABLE_FALLING_EDGE();

__HAL_RTC_WAKEUPTIMER_DISABLE(&hrtc);

/* Check and Clear the Wakeup flag if already set*/

if(__HAL_PWR_GET_FLAG(PWR_FLAG_WU) != RESET)

{

__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WU);

}

/* Check and Clear the Standby flag if already set*/

if(__HAL_PWR_GET_FLAG(PWR_FLAG_SB) != RESET)

{

__HAL_PWR_CLEAR_FLAG(PWR_FLAG_SB);

}

/* Check PWR Exti flag */

if(__HAL_PWR_PVD_EXTI_GET_FLAG() != RESET)

{

/* Clear PWR Exti pending bit */

__HAL_PWR_PVD_EXTI_CLEAR_FLAG();

}

__HAL_PWR_PVD_EXTI_ENABLE_RISING_EDGE();

HAL_PWR_EnableWakeUpPin(PWR_WAKEUP_PIN1); /* Allow wake up on rising edge + add pull down of 40ko on the pin */

  /*DBP : Enable access to Backup domain */

  HAL_PWR_EnableBkUpAccess();

  hrtc.Lock = HAL_UNLOCKED;

/* RTC_WAKEUPCLOCK_CK_SPRE_16BITS: clock config2, counter-- each second, interrupt when counter reach 0 */

/* At the end, the device shall wake-up every 12h (43200 seconds) to do a check up */

if(HAL_RTCEx_SetWakeUpTimer_IT(&hrtc,TimeToSleep, RTC_WAKEUPCLOCK_CK_SPRE_16BITS) != HAL_OK)

{

_Error_Handler(__FILE__, __LINE__);

}

hrtc.Lock = HAL_LOCKED;

/*DBP : Disable access to Backup domain */

HAL_PWR_DisableBkUpAccess();

__HAL_RTC_WAKEUPTIMER_ENABLE(&hrtc);

/* Enter to Standby mode */

HAL_PWR_EnterSTANDBYMode();

while (1)

{

}

//----------------------------------------------------------------------

If I use HAL_PWR_DisableWakeUpPin() in the first line, if PA0=1, the MCU always wakes up even if there is no rising edge.

How can I do to wake up with rising edge on PA0 and RTC without problem is PA0=1 when RTC wake up event occurs ?

Thanks for help.

Dams

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