【STM32】电源管理（PWR）

一、电源框图

二、低功耗模式（三种模式、进入、唤醒）

三、实现三种低功耗模式

1.睡眠模式

#include "key_led.h"
#include "bsp_exti.h"
#include "bsp_systick.h"int main(void)
{int i;SysTick_Configuration();Led_Configuration();PA0_EXTI0_Configuration();while (1) {for (i = 0; i < 10; i++) {GPIOA->ODR ^= GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4;Delay_us(500000);}__WFI();  //Wait for interrupt 等待任一中断唤醒}
}/* 睡眠模式，当任一中断唤醒 */
void EXTI0_IRQHandler(void)
{
}

2.停机模式

#include "key_led.h"
#include "bsp_exti.h"
#include "bsp_systick.h"int main(void)
{int i;SysTick_Configuration();Led_Configuration();PA0_EXTI0_Configuration();PA0_EXTI0_Configuration();while (1) {for (i = 0; i < 10; i++) {GPIOA->ODR ^= GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4;Delay_us(500000);}RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);PWR_EnterSTOPMode(PWR_Regulator_LowPower, PWR_STOPEntry_WFI);  //电压转换器进入低功耗模式，WFI进入停机模式//当任一中断唤醒时，系统时钟变为内部低速时钟，需要重新开启外部高速时钟（可直接在中断开启）while (1){GPIOA->ODR ^= GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4;Delay_us(500000);}}
}/* 设置系统时钟为外部高速时钟 */
static void SetSysClock_To72MHz(void)  //在启动函数md.s中，LDR     R0, =SystemInit，跳转查找此函数
{__IO uint32_t StartUpCounter = 0, HSEStatus = 0;/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/    /* Enable HSE */    RCC->CR |= ((uint32_t)RCC_CR_HSEON);/* Wait till HSE is ready and if Time out is reached exit */do{HSEStatus = RCC->CR & RCC_CR_HSERDY;StartUpCounter++;  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));if ((RCC->CR & RCC_CR_HSERDY) != RESET){HSEStatus = (uint32_t)0x01;}else{HSEStatus = (uint32_t)0x00;}  if (HSEStatus == (uint32_t)0x01){/* Enable Prefetch Buffer */FLASH->ACR |= FLASH_ACR_PRFTBE;/* Flash 2 wait state */FLASH->ACR &= (uint32_t)((uint32_t)~FLASH_ACR_LATENCY);FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_2;    /* HCLK = SYSCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* PCLK2 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;/* PCLK1 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV2;#ifdef STM32F10X_CL/* Configure PLLs ------------------------------------------------------*//* PLL2 configuration: PLL2CLK = (HSE / 5) * 8 = 40 MHz *//* PREDIV1 configuration: PREDIV1CLK = PLL2 / 5 = 8 MHz */RCC->CFGR2 &= (uint32_t)~(RCC_CFGR2_PREDIV2 | RCC_CFGR2_PLL2MUL |RCC_CFGR2_PREDIV1 | RCC_CFGR2_PREDIV1SRC);RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV5 | RCC_CFGR2_PLL2MUL8 |RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV5);/* Enable PLL2 */RCC->CR |= RCC_CR_PLL2ON;/* Wait till PLL2 is ready */while((RCC->CR & RCC_CR_PLL2RDY) == 0){}/* PLL configuration: PLLCLK = PREDIV1 * 9 = 72 MHz */ RCC->CFGR &= (uint32_t)~(RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | RCC_CFGR_PLLMULL);RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLXTPRE_PREDIV1 | RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLMULL9); 
#else    /*  PLL configuration: PLLCLK = HSE * 9 = 72 MHz */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE |RCC_CFGR_PLLMULL));RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSE | RCC_CFGR_PLLMULL9);
#endif /* STM32F10X_CL *//* Enable PLL */RCC->CR |= RCC_CR_PLLON;/* Wait till PLL is ready */while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* Select PLL as system clock source */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* Wait till PLL is used as system clock source */while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}}else{ /* If HSE fails to start-up, the application will have wrong clock configuration. User can add here some code to deal with this error */}
}/* 停机模式，当任一中断唤醒后，并将高速外部时钟再次开启 */
void EXTI0_IRQHandler(void)
{if (EXTI_GetITStatus(EXTI_Line0) != RESET) {SetSysClock_To72MHz();EXTI_ClearITPendingBit(EXTI_Line0);}
}

3.待机模式

#include "key_led.h"
#include "bsp_exti.h"
#include "bsp_systick.h"int main(void)
{SysTick_Configuration();Led_Configuration();PA5_EXTI5_Configuration();  //按下PA5产生中断，在中断函数中进入待机模式while (1) {GPIOA->ODR ^= GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4;Delay_us(500000);}
}void PA5_EXTI5_Configuration(void)
{NVIC_InitTypeDef NVIC_InitStructure;GPIO_InitTypeDef GPIO_InitStructure;EXTI_InitTypeDef EXTI_InitStructure;RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;NVIC_Init(&NVIC_InitStructure);GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;GPIO_Init(GPIOA, &GPIO_InitStructure);GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource5);EXTI_InitStructure.EXTI_Line = EXTI_Line5;EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;EXTI_InitStructure.EXTI_LineCmd = ENABLE;EXTI_Init(&EXTI_InitStructure);
}/* 在中断函数中进入待机模式 */
void EXTI9_5_IRQHandler(void)
{if (EXTI_GetITStatus(EXTI_Line5) != RESET) {PWR_WakeUpPinCmd(ENABLE);  //若使用WKUP引脚上的上升沿唤醒，在进入待机模式之前先使能WKUP引脚（WKUP对应PA0，需要给WKUP一个上升沿，即将PA0接到一个高电平3.3V）PWR_EnterSTANDBYMode();  //进入待机模式（被调用的函数：__WFI();）EXTI_ClearITPendingBit(EXTI_Line5);}
}