Posted on September 15, 2015 at 05:46
Hi,
I am running into issue where the device is locking up from time to time once STM32F427 is parked to stop mode.
Here is what I do it to park it to stop mode.
Please review the code snippet and let me know if I am missing anything or it is erroneous.
/* Make sure PWR peripheral is running */
RCC->APB1ENR |= RCC_APB1ENR_PWREN;
/* Back-up registers to be modified */
ADC1_CR2_c = ADC1->CR2;
ADC2_CR2_c = ADC2->CR2;
ADC3_CR2_c = ADC3->CR2;
DAC_CR_c = DAC->CR;
PWR_CR_c = PWR->CR;
/* Clear any pending external interrupts */
EXTI->PR = 0x007FFFFF;
if
(EXTI->PR == 0)
/* All pins are still quiet, we can go to sleep */
{
do
{
/* Disable SysTick Timer */
SysTick->CTRL &= 0xFFFFFFFE;
/* Disable each ADC (drivers must re-calibrate each ADC) */
ADC1->CR2 &= ~(ADC_CR2_ADON);
ADC2->CR2 &= ~(ADC_CR2_ADON);
ADC3->CR2 &= ~(ADC_CR2_ADON);
/* Disable each DAC (drivers must re-calibrate each DAC) */
DAC->CR &= ~(DAC_CR_EN1 | DAC_CR_EN2);
/* Voltage regulator in low power mode during stop mode */
PWR->CR |= PWR_CR_LPDS;
/* Enter Stop mode when the CPU enters deep sleep */
PWR->CR &= ~PWR_CR_PDDS;
/* Disable the Flash power down in low power mode */
PWR->CR &= ~PWR_CR_FPDS;
/* Clear the Wake up flag */
PWR->CR |= PWR_CR_CWUF;
/* Turn off misc clocks/clock sources */
RCC->BDCR &= ~( RCC_BDCR_LSEON |
// Disable LSE oscillator
RCC_BDCR_RTCSEL |
// Select no clock source for RTC
RCC_BDCR_RTCEN );
// Disable RTC
RCC->CSR &= ~RCC_CSR_LSION;
// Disable LSI oscillator
/* clear reset cause register */
RCC->CSR |= RCC_CSR_RMVF;
// Clear Reset cause flags
/* RTC Wake Up Timer & RTC ISR Configuration */
RTC_wakeup_setup(rtcWakeupTime);
systime_pause();
ENTER_CRITICAL();
/* Prepare to enter Cortex-M3/M4 DEEPSLEEP = STOP mode */
SCB->SCR |= SCB_SCR_SLEEPDEEP;
SCB->SCR &= ~SCB_SCR_SEVONPEND;
// use only enabled IRQs to wake-up
dsb();
nop();
wfi();
// Sweet dreams ... //now STM is waiting for interrupt only power button, charge completion, External power source and RTC interrupts are allowed in off mode
//in low power mode we allow Power button, trigger, charger connection and BT interrupts are allowe
nop();
nop();
nop();
SCB->SCR &= ~SCB_SCR_SLEEPDEEP;
// clear or wake from sleep/stop mode
/* Resume OS Tick (needed for OSTimeDly used in changeToPowerMode() */
systime_resume();
/* Start clocks, as any irq/task may be called after interrupts are enabled */
CLKGEN_init();
/* Enable interrupts to service RTC and OS Tick*/
EXIT_CRITICAL();
/* Clear the Wake up flag */
PWR->CR |= PWR_CR_CWUF;
}
while
(IsNoWakeupTriggered());
#stm32-power-management
