1 //定时器 5 通道 1 输入捕获配置
 2 TIM_ICInitTypeDef TIM5_ICInitStructure;
 3 void TIM5_Cap_Init(u16 arr,u16 psc)
 4 {
 5     GPIO_InitTypeDef GPIO_InitStructure;
 6     TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
 7     NVIC_InitTypeDef NVIC_InitStructure;
 8     RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE); //①使能 TIM5 时钟
 9 　　RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //①使能 GPIOA 时钟
10 　　//初始化 GPIOA.0 ①
11 　　GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; //PA0 设置
12 　　GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; //PA0 输入
13 　　GPIO_Init(GPIOA, &GPIO_InitStructure); //初始化 GPIOA.0
14 　　GPIO_ResetBits(GPIOA,GPIO_Pin_0); //PA0 下拉
15 　　//②初始化 TIM5 参数
16     TIM_TimeBaseStructure.TIM_Period = arr; //设定计数器自动重装值
17     TIM_TimeBaseStructure.TIM_Prescaler =psc; //预分频器
18     TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; // TDTS = Tck_tim
19     TIM_TimeBaseStructure.TIM_CounterMode =         TIM_CounterMode_Up; //TIM 向上计数模式
20     TIM_TimeBaseInit(TIM5, &TIM_TimeBaseStructure); //初始化 TIMx
21 　　//③初始化 TIM5 输入捕获通道 1
22     TIM5_ICInitStructure.TIM_Channel = TIM_Channel_1; //选择输入端 IC1 映射到 TI1 上
23     TIM5_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising; //上升沿捕获
24     TIM5_ICInitStructure.TIM_ICSelection =                 TIM_ICSelection_DirectTI; //映射到 TI1 上
25     TIM5_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //配置输入分频,不分频
26     TIM5_ICInitStructure.TIM_ICFilter = 0x00; //IC1F=0000 配置输入滤波器 不滤波
27     TIM_ICInit(TIM5, &TIM5_ICInitStructure); //初始化 TIM5 输入捕获通道 1
28 　　//⑤初始化 NVIC 中断优先级分组
29     NVIC_InitStructure.NVIC_IRQChannel = TIM5_IRQn; //TIM3 中断
30     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //先占优先级 2 级
31     NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //从优先级 0 级
32     NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ 通道被使能
33     NVIC_Init(&NVIC_InitStructure); //初始化 NVIC
34     TIM_ITConfig( TIM5,TIM_IT_Update|TIM_IT_CC1,ENABLE);//④允许更新中断捕获中断
35     TIM_Cmd(TIM5,ENABLE ); //⑥使能定时器 5
36 }
37