STM32输入捕获控制测量频率方法程序

stm32输入捕获配置

void TIM3_Confguration()

{ TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;

TIM_ICInitTypeDef TIM_ICInitStructure;

/* Time base configuration */

TIM_TimeBaseStructure.TIM_Period = 1000; // 这两句for 1ms，stm32 有72Mhz，先72分频，再计数到1000=1ms

TIM_TimeBaseStructure.TIM_Prescaler = 72;

TIM_TimeBaseStructure.TIM_ClockDivision = 0;

TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //上升沿计数

TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

/* Clear TIM2 update pending flag[清除TIM2溢出中断标志] */

TIM_ClearFlag(TIM3, TIM_FLAG_Update);

/* Enable TIM3 Update interrupt [TIM3溢出中断允许]*/

TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE); //以上配置的意思是1ms产生一个中断

TIM_ICInitStructure.TIM_Channel = TIM_Channel_1; // Channel_1

TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising; //choose rising edge选择上升沿

TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //Direct connecte直接连接

TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //预分频器register every

rising edages

TIM_ICInitStructure.TIM_ICFilter = 0x03; //used 3 period to wait for 系统信号接收正常TIM_ICInit(TIM3, &TIM_ICInitStructure);

TIM_SelectInputTrigger(TIM3, TIM_TS_TI1FP1 ); //选择时钟触发源，这里只能用1或2，意味着通道34不能用输入触发（Trigger）

TIM_SelectSlaveMode(TIM3, TIM_SlaveMode_Reset);//触发方式

TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable); //启动定时器的被动触发

TIM_SetCompare1(TIM3, 0); //设置捕获计数器初值

/* TIM3 enable counter */

TIM_ClearITPendingBit(TIM3, TIM_IT_Update );

TIM_ClearITPendingBit(TIM3, TIM_IT_CC1);

TIM_Cmd(TIM3, ENABLE);

}

/* Enable the TIM3 gloabal Interrupt [允许TIM3全局中断]*/

NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQChannel;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 4;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3 ，ENABLE）；

//PA6 for TIM3 channel 1

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;

GPIO_Init(GPIOA, &GPIO_InitStructure);