Posted on January 28, 2014 at 13:47
the counter receives the write value, but it doesnt start when i enable the wake up event. The WUTF bit should be set when the counter reaches 0, but this never happens.
void init_RTC(void)
{
/* Enable the PWR clock */
RCC->APB1ENR |= (1UL <<
28
);
/* Allow access to RTC */
PWR->CR |= (1UL <<
8
);
/* Select the Clock source LSE or LSI */
select_LSEclk();
//select_LSIclk();
/* Enable the RTC */
RCC->BDCR |= (1UL <<
15
);
/* Set the RTC time */
/* wait for RTC register APB synchronisation */
while((RTC->ISR & (1UL <<
5
)) == 0)
{
}
/* Turn on LED to verify RTC is working (DEBUG) */
LED_On(1);
}
/**************************************************************************
LSE
Initialize the RTC using an external clock source LSE 768 kHz
crystal oscillator. This clock source has the lowest power consumption
***************************************************************************/
void select_LSEclk(void) {
/* Select the clock source: using LSE 32 kHz as the RTC clock
Enable the RTC clock assuming it has the correct prescaler provided */
RCC->BDCR |= 0x1;
/* Wait til LSE is ready */
while((RCC->BDCR & (1UL <<
1
)) == 0)
{
/* Do nothing while crystal is not ready */
}
/* Select the RTC clock source to LSE */
RCC->BDCR |= (1UL <<
8
);
}
/**************************************************************************
LSI
Initialize the RTC using an internal clock source LSI 32 kHz
crystal oscillator.
***************************************************************************/
void select_LSIclk(void) {
/* Select the clock source: using LSI 32 kHz as the RTC clock
Enable the RTC clock assuming it has the correct prescaler provided */
RCC->CSR |= 0x1;
/* Wait til LSI is ready */
while((RCC->CSR & (1UL <<
1
)) == 0)
{
/* Do nothing while crystal is not ready */
}
/* Select the RTC clock source to LSI */
RCC->BDCR |= (1UL <<
9
);
}
/*************************************************************************
Initialising the Auto-wakeup unit for a periodic wakeup event, 0x39
should initialise the counter for 30 mins
Do we want to enable the wakeup timer interrupt??
**************************************************************************/
void init_autowakeup(void)
{
/* Allow access to RTC */
PWR->CR |= (1UL <<
8
);
/* Disable the RTC registers Write protection */
rtc_write_enable();
/* Disable Wakeup Counter */
RTC_WakeUpCmd(DISABLE);
/* Ensure access to Wakeup auto-reload
counter and bits WUCKSEL[2:0] is allowed.
Poll WUTWF until it is set in RTC_ISR (takes 2 RTCCLK cycles) */
while((RTC->ISR & (1UL <<
2
)) == 0)
{
}
RTC_WKUP_IRQHandler();
/* Enable the RTC registers write protection */
rtc_write_disable();
/* Enable Wakeup Counter */
RTC_WakeUpCmd(ENABLE);
LED_On(3);
}
/*************************************************************************
Enable the wakeup event interrupt.
EXTI line 22 is connected to the RTC Wakeup event
**************************************************************************/
void RTC_WKUP_IRQHandler(void)
{
EXTI_InitTypeDef EXTI_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RTC_WakeUpClockConfig(RTC_WakeUpClock_CK_SPRE_16bits);
RTC_SetWakeUpCounter(0x000F);
//RTC_SetWakeUpCounter(0x1FFF);
/* Enable WUTIE wake up interrupt enabled */
//RTC->CR |= (1UL << 14);
/* 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);
}
thanks
