stm32F0Timer2定时中断问题

gcm_081

void Tim2_Config(void)
{
  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2 , ENABLE); //使能Tim2时钟

// TIM_DeInit(TIM2);
// TIM_InternalClockConfig(TIM2);
  TIM_TimeBaseStructure.TIM_Prescaler = 48000-1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = 0x50;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
// TIM2->SR &= (uint16_t)~(1<<0);



TIM_ClearFlag(TIM2,TIM_FLAG_Update);
TIM_ClearITPendingBit(TIM2,TIM_IT_Update);

// TIM_ARRPreloadConfig(TIM2, DISABLE);
TIM_ITConfig(TIM2,TIM_IT_Update,ENABLE);

NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPriority = 0x0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

TIM_Cmd(TIM2, DISABLE);  //初始化的时候先关闭tim2
}

中断服务函数

void TIM2_IRQHandler(void)
{
// uint16_t Tim2_CNT;
if(TIM_GetFlagStatus(TIM2,TIM_IT_Update)!=RESET)
{

// Tim2_CNT = TIM_GetCounter(TIM2);
// TIM2->SR &= (uint16_t)~(1<<0);
TIM_ClearFlag(TIM2,TIM_IT_Update);
TIM_ClearITPendingBit(TIM2,TIM_IT_Update);

TIM_Cmd(TIM2, DISABLE);
}
}
启动定时后，进入两次中断后才清除中断标志位，大家帮我看看到底怎么回事了呢，我折腾了两天了，实在看不出来怎么回事了呢

正点原子

帮顶。。。。。