EEPW论坛

本来想做个输出PWM波实验的，家里没有示波器。就做个基础的定时功能。采用的通用定时器TIM2来计时，并让LED等闪烁，突然觉得LED好有用啊。对于捕获比较功能暂时没有测试。STM32有的，GD32都有，这里也是直接采用STM32的固件库来完成代码。

1、初始化通用定时器2

void  TimerInit(u16 arr,u16 psc)
{
    TIM_TimeBaseInitTypeDef  TIM_TimeBaseInitStruct;
	  NVIC_InitTypeDef  NVIC_InitStruct;
	  RCC_APB1PeriphClockCmd (RCC_APB1Periph_TIM2,ENABLE );
	  TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
	  TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;
	  TIM_TimeBaseInitStruct.TIM_Period = arr;
	  TIM_TimeBaseInitStruct.TIM_Prescaler = psc;
	  TIM_TimeBaseInit (TIM2,&TIM_TimeBaseInitStruct);
	  TIM_ITConfig (TIM2,TIM_IT_Update,ENABLE );
	  NVIC_InitStruct.NVIC_IRQChannel = TIM2_IRQn;
	  NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
	  NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 2;
	  NVIC_InitStruct.NVIC_IRQChannelSubPriority = 1;
	  NVIC_Init(&NVIC_InitStruct);
	  TIM_Cmd (TIM2,ENABLE);

}

void  TIM2_IRQHandler()
{
    if(TIM_GetITStatus (TIM2,TIM_IT_Update) == SET)
		{
         gLedRunFlag ^= 1;
			   TIM_ClearITPendingBit (TIM2,TIM_IT_Update);
    }
}

int main()
{
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
	LedPinInit();
	TimerInit(4999,7199);  //500ms
	while(1)
	{
      if(gLedRunFlag != gLastLedFlag)
      {
         LedPowerSelect(gLedRunFlag);
				 gLastLedFlag = gLedRunFlag;
      }				
	}
}