PWM输入捕获不了

只看该作者 · 2013-7-21 21:27

我PWM输入捕获不了,总是乱码一堆,贴代码:
void PWM_cap()
{
TIM_ICInitTypeDef timic;
GPIO_InitTypeDef gpio;
TIM_TimeBaseInitTypeDef timebase;
NVIC_InitTypeDef nvic;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5,ENABLE);

gpio.GPIO_Mode = GPIO_Mode_IN_FLOATING;
gpio.GPIO_Pin = GPIO_Pin_0;
GPIO_Init(GPIOA,&gpio);

timebase.TIM_Period = 0xffff;
timebase.TIM_Prescaler = 71;
timebase.TIM_ClockDivision = 0;
timebase.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM5,&timebase);

timic.TIM_Channel = TIM_Channel_1;
timic.TIM_ICFilter = 0;
timic.TIM_ICPolarity = TIM_ICPolarity_Falling;
timic.TIM_ICPrescaler = TIM_ICPSC_DIV1;
timic.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM_PWMIConfig(TIM5,&timic);

nvic.NVIC_IRQChannel = TIM5_IRQn;
nvic.NVIC_IRQChannelPreemptionPriority = 0;
nvic.NVIC_IRQChannelSubPriority = 0;
nvic.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&nvic);
TIM_Cmd(TIM5,ENABLE);
TIM_ITConfig(TIM5,TIM_IT_CC1,ENABLE);
}

void TIM5_IRQHandler()
{
   int pl,zkb;
  pl = TIM_GetCapture1(TIM5);
  zkb = TIM_GetCapture2(TIM5);
  zkb = zkb *100/pl;
  pl = 1000000/pl;
   Nokia_5110_int2str(zkb,0,0);
   Nokia_5110_int2str(pl,0,2);
   Nokia_5110_int2str(123,0,5);
  pl=0;
  zkb=0;
  TIM_ClearITPendingBit(TIM3, TIM_IT_CC1);

}
哪位朋友能给指点一下.

只看该作者 · 2013-7-21 22:14

1、首先指出一个问题：最后一句应该是 TIM_ClearITPendingBit(TIM5, TIM_IT_CC1);
2、可行性代码：楼主可以这样配置Timer5:

//初始化定时器5 TIM5
TIM_TimeBaseStructure.TIM_Period = 0xFFFF-1; //设定计数器自动重装值
TIM_TimeBaseStructure.TIM_Prescaler =72-1; //预分频器
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0; //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(TIM5, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

//初始化TIM5输入捕获参数
TIM5_ICInitStructure.TIM_Channel = TIM_Channel_1; //CC1S=01(对应PA0) 选择输入端 IC1映射到TI1上
    TIM5_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising; //上升沿捕获
    TIM5_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //映射到TI1上
    TIM5_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;    //配置输入分频,不分频
    TIM5_ICInitStructure.TIM_ICFilter = 0x00;//IC1F=0000 配置输入滤波器不滤波
    TIM_ICInit(TIM5, &TIM5_ICInitStructure);
TIM_SelectInputTrigger(TIM5, TIM_TS_TI1FP1);             //选择IC2为始终触发源
TIM_SelectSlaveMode(TIM5, TIM_SlaveMode_Reset);//TIM从模式：触发信号的上升沿重新初始化计数器和触发寄存器的更新事件
TIM_SelectMasterSlaveMode(TIM5, TIM_MasterSlaveMode_Enable); //启动定时器的被动触发

TIM_ITConfig(TIM5,TIM_IT_CC1,ENABLE);//允许CC1IE捕获中断
   TIM_Cmd(TIM5,ENABLE ); //使能定时器5