The STM32F479II is set to standby mode and activated by PWR_WAKEUP_PIN1. This all works. But there is one situation where it wakes up immediately. The next standby works however.
How to reproduce:
Power Cycle -> RTC has no battery thus date and time is reset -> call HAL_RTC_SetTime -> set to standby -> the application is started again (but not the bootloader)
It does not wake up, if is sent to standby the second time.
It does also not wake up if only HAL_RTC_SetDate is called.
I does also wake up if the stlink is connected to the uart and the usb is connected to power
EDIT:
The problem does not occur, if i comment out this in the HAL_RTC_SetTime (see mur_disablethefollowing below):
/* Configure the RTC_CR register (Deprecated. Use HAL_RTC_DST_*** functions instead) */
hrtc->Instance->CR |= (uint32_t)(sTime->DayLightSaving | sTime->StoreOperation);
HAL_StatusTypeDef HAL_RTC_SetTime(RTC_HandleTypeDef *hrtc, RTC_TimeTypeDef *sTime, uint32_t Format)
{
uint32_t tmpreg = 0U;
HAL_StatusTypeDef status;
/* Check the parameters */
assert_param(IS_RTC_FORMAT(Format));
assert_param(IS_RTC_DAYLIGHT_SAVING(sTime->DayLightSaving));
assert_param(IS_RTC_STORE_OPERATION(sTime->StoreOperation));
/* Process Locked */
__HAL_LOCK(hrtc);
hrtc->State = HAL_RTC_STATE_BUSY;
if (Format == RTC_FORMAT_BIN)
{
if ((hrtc->Instance->CR & RTC_CR_FMT) != 0U)
{
assert_param(IS_RTC_HOUR12(sTime->Hours));
assert_param(IS_RTC_HOURFORMAT12(sTime->TimeFormat));
}
else
{
sTime->TimeFormat = 0x00U;
assert_param(IS_RTC_HOUR24(sTime->Hours));
}
assert_param(IS_RTC_MINUTES(sTime->Minutes));
assert_param(IS_RTC_SECONDS(sTime->Seconds));
tmpreg = (uint32_t)(( (uint32_t)RTC_ByteToBcd2(sTime->Hours) << RTC_TR_HU_Pos) | \
( (uint32_t)RTC_ByteToBcd2(sTime->Minutes) << RTC_TR_MNU_Pos) | \
( (uint32_t)RTC_ByteToBcd2(sTime->Seconds)) | \
(((uint32_t)sTime->TimeFormat) << RTC_TR_PM_Pos));
}
else
{
if ((hrtc->Instance->CR & RTC_CR_FMT) != 0U)
{
assert_param(IS_RTC_HOUR12(RTC_Bcd2ToByte(sTime->Hours)));
assert_param(IS_RTC_HOURFORMAT12(sTime->TimeFormat));
}
else
{
sTime->TimeFormat = 0x00U;
assert_param(IS_RTC_HOUR24(RTC_Bcd2ToByte(sTime->Hours)));
}
assert_param(IS_RTC_MINUTES(RTC_Bcd2ToByte(sTime->Minutes)));
assert_param(IS_RTC_SECONDS(RTC_Bcd2ToByte(sTime->Seconds)));
tmpreg = (((uint32_t)(sTime->Hours) << RTC_TR_HU_Pos) | \
((uint32_t)(sTime->Minutes) << RTC_TR_MNU_Pos) | \
((uint32_t) sTime->Seconds) | \
((uint32_t)(sTime->TimeFormat) << RTC_TR_PM_Pos));
}
/* Disable the write protection for RTC registers */
__HAL_RTC_WRITEPROTECTION_DISABLE(hrtc);
/* Enter Initialization mode */
status = RTC_EnterInitMode(hrtc);
if (status == HAL_OK)
{
/* Set the RTC_TR register */
hrtc->Instance->TR = (uint32_t)(tmpreg & RTC_TR_RESERVED_MASK);
/* Clear the bits to be configured (Deprecated. Use HAL_RTC_DST_*** functions instead) */
hrtc->Instance->CR &= (uint32_t)~RTC_CR_BKP;
#define mur_disablethefollowing
#ifndef mur_disablethefollowing
/* Configure the RTC_CR register (Deprecated. Use HAL_RTC_DST_*** functions instead) */
hrtc->Instance->CR |= (uint32_t)(sTime->DayLightSaving | sTime->StoreOperation);
#endif
/* Exit Initialization mode */
status = RTC_ExitInitMode(hrtc);
}
if (status == HAL_OK)
{
hrtc->State = HAL_RTC_STATE_READY;
}
/* Enable the write protection for RTC registers */
__HAL_RTC_WRITEPROTECTION_ENABLE(hrtc);
/* Process Unlocked */
__HAL_UNLOCK(hrtc);
return status;
}
power_off:
void power_off()
{
(void) HAL_RTCEx_DeactivateWakeUpTimer(&hrtc);
HAL_PWR_DisableWakeUpPin(PWR_WAKEUP_PIN1);
__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WU);
__HAL_RTC_WAKEUPTIMER_CLEAR_FLAG(&hrtc, RTC_FLAG_WUTF);
HAL_PWR_EnableWakeUpPin(PWR_WAKEUP_PIN1);
__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WU);
HAL_PWR_EnterSTANDBYMode();
}
