请教用STM32_TIM2定时出现两个中断？

只看该作者 · 2011-12-10 19:41

请教  用STM32_TIM2向上计数定时时出现两个中断？

void TIM_Configuration(void)
{
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
//  TIM_OCInitTypeDef  TIM_OCInitStructure;
  /* Time base configuration */
  TIM_TimeBaseStructure.TIM_Period = 20000;
  TIM_TimeBaseStructure.TIM_Prescaler = 35999;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;//==TIM_CKD_DIV1
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

////
  TIM_ARRPreloadConfig(TIM2, DISABLE);

//清中断，以免一启用中断后立即产生中断
  TIM_ClearFlag(TIM2, TIM_FLAG_Update);
/* TIM enable counter */
  TIM_Cmd(TIM2, ENABLE);

  TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);

中断向量配置代码：
void NVIC_Configuration(void)
{
  NVIC_InitTypeDef NVIC_InitStructure;

#ifdef  VECT_TAB_RAM
  /* Set the Vector Table base location at 0x20000000 */
  NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
#else  /* VECT_TAB_FLASH  */
  /* Set the Vector Table base location at 0x08000000 */
  NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);
#endif

  /* Enable the USART1 Interrupt */
  NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

  /* Enable the TIM2 global Interrupt */
  NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

}

这是中断部分的代码
void TIM2_IRQHandler(void)
{

//
if(TIM_GetITStatus(TIM2, TIM_IT_Update) == SET)
//
{

time2++;

USART_SendData(USART1,time2);

while(USART_GetFlagStatus(USART1, USART_FLAG_TC)==RESET);    //判断是否发送完成。

/* Clear the TIM3 update interrupt pending bit */

TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
//
}
}

运行时每次在pc的串口上都会收到两个连续的数
如果把代码改成
void TIM2_IRQHandler(void)
{

time2++;

if(TIM_GetITStatus(TIM2, TIM_IT_Update) == SET)

{
//
time2++;

USART_SendData(USART1,time2);

while(USART_GetFlagStatus(USART1, USART_FLAG_TC)==RESET);    //判断是否发送完成。

/* Clear the TIM3 update interrupt pending bit */

TIM_ClearITPendingBit(TIM2, TIM_IT_Update);

}
}

则在PC串口上只能有道奇数？？？？？求解？？
这些天在看《STM32技术参考手册中文翻译第10版》的TIMx 说实话，有点像看日文，完全找不到系统的把握，希望那位前辈有好的资料共享一下，小菜在此谢谢了！！！！！！！！！！！！！！！！！