定时器的时钟源选择ETR问题？

wanrenqi

void TIM1_init(void)
{
TIM_TimeBaseInitTypeDef   TIM_TimeBaseStructure;
GPIO_InitTypeDef          GPIO_InitStructure;
  NVIC_InitTypeDef          NVIC_InitStructure;

RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOA|RCC_APB2Periph_AFIO,ENABLE); 

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
GPIO_Init(GPIOA, &GPIO_InitStructure);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);          //?????¨?±?÷?±??
TIM_DeInit(TIM1);

TIM_SetClockDivision(TIM1,TIM_CKD_DIV1);                      //?è?????¨?????????ò???????????¨??×?3
TIM_ETRClockMode2Config(TIM1, TIM_ExtTRGPSC_OFF,TIM_ExtTRGPolarity_Inverted,3);
                             
TIM_TimeBaseStructure.TIM_Period   = 5-1;              // ×?????×°????????5
TIM_TimeBaseStructure.TIM_Prescaler = 1-1;                //??·???
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;       //?¨?±?÷?±???????¨APB1?©????×????¨?÷?®????·???±????¨?±?÷????????????????
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);

TIM_ARRPreloadConfig(TIM1,DISABLE);                           //×?????×°???????÷???¤×°????????

NVIC_InitStructure.NVIC_IRQChannel =  TIM_IT_Update;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;   //???????¨?±?÷1???ü?????????ò???????ò???¨?±?÷1???ü??????
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure); 
     
TIM_Cmd(TIM1, ENABLE);

TIM_UpdateRequestConfig(TIM1, TIM_UpdateSource_Regular);  /* ?ü?????ó???????????????????÷???????ò?????ú?ú?ü?????? */
TIM_ClearFlag(TIM1,TIM_IT_Update);
TIM_ITConfig(TIM1, TIM_IT_Update, ENABLE);

}

/**********************************************************
**????????   LED_Init
**?????????? ??
**??????????  ??
**·???????    
**???????÷??  
**********************************************************/
void LED_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB ,ENABLE);

GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_1;               /* ??????Speak??IO?? */    
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_Out_PP;
GPIO_Init(GPIOB, &GPIO_InitStructure);
  GPIO_ResetBits(GPIOB,GPIO_Pin_1 );
}

/***********************************************************/
/* ?????????????????????ò*/
/* ???????÷?????ò*/
/***********************************************************/
void TIM1_IRQHandler(void)
{
//   if(TIM_GetITStatus(TIM1,TIM_IT_Trigger)) 
// {
// TIM_ClearITPendingBit(TIM1,TIM_IT_Trigger);
//   LED=~LED;
//   }

if(TIM_GetITStatus(TIM1,TIM_IT_Update)) 
{
TIM_ClearITPendingBit(TIM1,TIM_IT_Update);
    LED=~LED;
  }
}

为什么没有闪烁

styleno1

你还没说你的疑问呢，就这么页代码？

wanrenqi

回复【2楼】styleno1:
---------------------------------灯没有闪烁，没有更新中断产生