STM32定时器4外部触发求助

bin65530 · 发表于 2013-2-1 20:08:24

在定时器4的CH4输入一脉冲信号，在上升沿时触发定时器开始从0向上计数，记到TIM_Period时产生中断，该怎么设置啊？下面是我弄的初始化程序，搞了半天都不行，请原子哥帮看看啊！
void TIM4_Int_Init(void)
{
          TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
// TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_ICInitTypeDef TIM_ICInitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB ,ENABLE);
         //GPIOB端口初始化
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 ;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD;   //下拉输入
        GPIO_Init(GPIOB, &GPIO_InitStructure);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE); //时钟使能

//定时器TIM4初始化
TIM_TimeBaseStructure.TIM_Period = 10000; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值1000*720/72=10000us=10ms
TIM_TimeBaseStructure.TIM_Prescaler =71; //设置用来作为TIMx时钟频率除数的预分频值
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位
TIM_ARRPreloadConfig(TIM2, ENABLE);//禁止ARR预装载缓冲器
TIM_ITConfig(TIM4,TIM_IT_Update,ENABLE ); //使能指定的TIM4中断,允许更新中断

//TIM_ICStructInit(&TIM_ICInitStructure); /* TIM4配置在输入捕获模式 */

      TIM_ICInitStructure.TIM_Channel = TIM_Channel_4;
      TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
      TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
      TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
      TIM_ICInitStructure.TIM_ICFilter = 0;
      TIM_ICInit(TIM4, &TIM_ICInitStructure);

TIM_SelectInputTrigger(TIM4, TIM_TS_ETRF); //输入触发选择
TIM_SelectSlaveMode(TIM4, TIM_SlaveMode_Trigger);//从模式选择:触发模式

//中断优先级NVIC设置
NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn; //TIM4中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //先占优先级0级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1; //从优先级3级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
NVIC_Init(&NVIC_InitStructure); //初始化NVIC寄存器

TIM_Cmd(TIM4, ENABLE); //使能TIMx