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源码

void tim3_init(void)
{
	NVIC_InitTypeDef NVIC_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;


	//使能TIM3的硬件时钟
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);
	//配置TIM3的定时时间
	TIM_TimeBaseStructure.TIM_Period = 10000-1;  //自动重载
	TIM_TimeBaseStructure.TIM_Prescaler = 8400-1;   //预分频值为8400    84000000/8400=10000(1S)
	TIM_TimeBaseStructure.TIM_ClockDivision = 0;
	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //从0开始计数，然后计数到TIM_Period这个值就触发中断

	TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
	
	
	//配置TIM3的中断触发：时间更新
	TIM_ITConfig(TIM3,TIM_IT_Update, ENABLE);
	
	//配置TIM3的优先级
	NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;  //中断号
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;   //抢占优先级
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;      //响应优先级
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;    //打开通道给NVIC管理
	NVIC_Init(&NVIC_InitStructure);
	
	//使能TIM3工作
	TIM_Cmd(TIM3, ENABLE);
}

void TIM3_IRQHandler(void)
{
	
	if(TIM_GetITStatus(TIM3,TIM_IT_Update) == SET)
	{
		
		PFout(9)^=1;	
		
		//告诉CPU，已经完成接收中断请求，可以响应新的接收中断请求
		TIM_ClearITPendingBit(TIM3,TIM_IT_Update);
	
	}

}

其他外设定时器使用方法

打开对应时钟供电