Posted on August 17, 2014 at 15:34 Hello,I'm currently quiet frustratedI'm trying to set up with the RTC wakeUp register an interrupt of 128Hz. For the RTC the LSI is used (I know not very precisely but for current testing propuse its enough)here is my code I use:
void
init()
{
RTC_InitTypeDef RTC_InitStructure;
EXTI_InitTypeDef EXTI_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable the PWR clock */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);
/* Allow access to RTC */
PWR_BackupAccessCmd(ENABLE);
/* Enable the LSI OSC */
RCC_LSICmd(ENABLE);
/* Wait till LSI is ready */
while
(RCC_GetFlagStatus(RCC_FLAG_LSIRDY) == RESET)
{
}
/* Select the RTC Clock Source */
RCC_RTCCLKConfig(RCC_RTCCLKSource_LSI);
/* Configure the RTC data register and RTC prescaler */
RTC_InitStructure.RTC_AsynchPrediv = 0x7F;
// prescaler set to optain a 1 Hz signal of the 32kHz LSI
RTC_InitStructure.RTC_SynchPrediv = 0xFF;
// prescaler set to optain a 1 Hz signal of the 32kHz LSI
RTC_InitStructure.RTC_HourFormat = RTC_HourFormat_24;
/* Check on RTC init */
if
(RTC_Init(&RTC_InitStructure) == ERROR)
{
return
;
}
/* Enable the RTC Clock */
RCC_RTCCLKCmd(ENABLE);
/* Wait for RTC APB registers synchronisation */
RTC_WaitForSynchro();
RTC_WakeUpClockConfig(RTC_WakeUpClock_RTCCLK_Div16);
RTC_SetWakeUpCounter(0x10);
/* Enable the Wakeup Interrupt */
RTC_ITConfig(RTC_IT_WUT, ENABLE);
/* Connect EXTI_Line22 to the RTC Wakeup event */
EXTI_ClearITPendingBit(EXTI_Line22);
EXTI_InitStructure.EXTI_Line = EXTI_Line22;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
/* Enable the RTC Wakeup Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = RTC_WKUP_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Enable Wakeup Counter */
RTC_WakeUpCmd(ENABLE);
}
void
RTC_WKUP_IRQHandler(
void
)
{
doSomething();
// Interrupt Flags loeschen
RTC_ClearITPendingBit(RTC_IT_WUT);
EXTI_ClearITPendingBit(EXTI_Line22);
}
}
I'm using GCC 4.7.3 with the code above the
RTC_WKUP_IRQHandler
is never calledwhen I put a
''RTC_ClearITPendingBit(RTC_IT_WUT);'' at the end of
init() my
RTC_WKUP_IRQHandler is still never called but the whole programms hangs in
''def_irq_handler RTC_WKUP_IRQHandler
'' defined in the file
startup_stm32f4xx.S I think because the
RTC_IT_WUT flag is never cleared
