stm32的可编程电压检测PVD

配置PVD的顺序如：

注意一般使能PVD在系统初始化完毕开启。

/**
  * @brief  Configures EXTI Lines.
  * @param  None
  * @retval None
  */
static void EXTI_Configuration(void)
{
  EXTI_InitTypeDef EXTI_InitStructure;

  /* Configure EXTI Line16(PVD Output) to generate an interrupt on rising and
     falling edges */
  EXTI_ClearITPendingBit(EXTI_Line16);
  EXTI_InitStructure.EXTI_Line = EXTI_Line16;
  EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
  EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising_Falling;
  EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  EXTI_Init(&EXTI_InitStructure);

}

/**
  * @brief  Configures NVIC and Vector Table base location.
  * @param  None
  * @retval None
  */
static void NVIC_Configuration(void)
{
  NVIC_InitTypeDef NVIC_InitStructure;
  
  /* Configure one bit for preemption priority */
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
  
  /* Enable the PVD Interrupt */
  NVIC_InitStructure.NVIC_IRQChannel = PVD_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}

static void RCC_Configuration(void)
{
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR | RCC_APB1Periph_BKP, ENABLE);
}

void my_PVD_Configuration(void)
{
	RCC_Configuration();	
	EXTI_Configuration();
	NVIC_Configuration();

	PWR_PVDLevelConfig(PWR_PVDLevel_2V4);
  	//PWR_PVDCmd(ENABLE);						 //PVD使能的一般是在系统初始化完毕后开启
}