I try to use standby mode on STM32L071. I slightly modified my code that worked fine on STM32L452RE. I use RTC wakeup and RTC alarms to be sure it will wake up (if RTC wakeup fails, 5 second later is ALARM A then 5 second later ALARM B)
Code below. nailesekund equals 60, timerega is set up for 65 seconds from current time, timeregb is set up 70 seconds from current time. Checked - values are OK.
RCC_APB1ENR|=0x10000400; FLUSH;
while(konsola_active) asm("wfi"); //waits for all pending characters transmitted on serial port
CORTEX_SCR=0x04; // deep sleep enable
PWR_CR=0x11A03;
RCC_AHB2ENR|=0x7; FLUSH;
GPIOA[GPIO_MODER]=0xFFFFFFFF;
GPIOB[GPIO_MODER]=0xFFFFFFFF;
GPIOC[GPIO_MODER]=0xFFFFFFFF;
GPIOD[GPIO_MODER]=0xFFFFFFFF;
GPIOE[GPIO_MODER]=0xFFFFFFFF;
GPIOH[GPIO_MODER]=0xF;
GPIOA[GPIO_PUPDR]=0;
GPIOB[GPIO_PUPDR]=0;
GPIOC[GPIO_PUPDR]=0;
GPIOD[GPIO_PUPDR]=0;
GPIOE[GPIO_PUPDR]=0;
GPIOH[GPIO_PUPDR]=0;
FLUSH; RCC_IOPENR&=~0x9F;
RTC_WPR=0xCA; RTC_WPR=0x53; FLUSH;
RTC_ISR&=7; //czyszczenie wszystkich flag przerwań
while(7!=(RTC_ISR&7)); //pozwolenie na zmiane rejestru wakeup timera i alarmów
RTC_WUTR=nailesekund; //po tym czasie ma wakeup timer zadziałać
RTC_ALRMAR=timerega|0x80000000;
RTC_ALRMBR=timeregb|0x80000000;
RTC_CR=0x7724; //wakeup timer+wakeup timer interrupt enable, wakeup timer liczony sekundami, alarm a i b
RTC_ISR&=7;
FLUSH; RTC_WPR=0; FLUSH;
PWR_CR&=~(1<<8); FLUSH; //zablokowanie ustawień RTC
RCC_APB1ENR&=~0x10000400; //wyłączenie taktowania RTC, PWR
NVIC_ICER=0xFFFFFFFF;
//EXTI 20 RTC_WAKEUP 17 RTC_ALARM
//dorobić jeszcze reakcje na kontaktron!
EXTI_FTSR=EXTI_RTSR=EXTI_IMR=(1<<20)|(1<<17);
FLUSH;
while(1) asm("wfi");
the result is that processor enters standby mode forever.
Very similar code worked fine for STM32L452 - CPU woke up after 60 seconds
Thank you for any help.
