stm32f103STM1 输入捕获测量频率 占空比 波长 代码

以下是使用STM32F103微控制器进行输入捕获测量频率、占空比和波长的示例代码：

#include "stm32f10x.h"

#define TIMER_PRESCALER 72
#define PULSE_PERIOD 2000 // 2ms

uint32_t pulse_start_time = 0;
uint32_t pulse_end_time = 0;
float frequency = 0;
float duty_cycle = 0;
float wavelength = 0;

void TIM2_IRQHandler(void)
{
    if(TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET)
    {
        if(pulse_start_time == 0)
        {
            pulse_start_time = TIM_GetCapture1(TIM2);
        }
        else
        {
            pulse_end_time = TIM_GetCapture1(TIM2);
            frequency = (float)TIMER_PRESCALER / (pulse_end_time - pulse_start_time);
            duty_cycle = (float)(pulse_end_time - pulse_start_time) / PULSE_PERIOD * 100;
            wavelength = frequency == 0 ? 0 : 1 / frequency;
            pulse_start_time = 0;
            pulse_end_time = 0;
        }
        TIM_ClearITPendingBit(TIM2, TIM_IT_CC1);
    }
}

void TIM2_Configuration(void)
{
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
    TIM_TimeBaseStructure.TIM_Period = PULSE_PERIOD - 1;
    TIM_TimeBaseStructure.TIM_Prescaler = TIMER_PRESCALER - 1;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

    TIM_OCStructInit(&TIM_OCInitStructure);
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = PULSE_PERIOD / 2 - 1;
    TIM_OC1Init(TIM2, &TIM_OCInitStructure);

    TIM_ITConfig(TIM2, TIM_IT_CC1, ENABLE);
    TIM_Cmd(TIM2, ENABLE);

    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

int main(void)
{
    TIM2_Configuration();

    while(1)
    {
        // Your code here
    }
}

在这个示例代码中，我们将TIM2定时器配置为PWM输出模式，并启用输入捕获来捕获PWM脉冲的上升沿和下降沿时间。当捕获到下降沿时间时，我们可以计算出频率、占空比和波长，并将它们存储在相应的变量中。请注意，示例代码中的PWM周期为2ms，可以根据实际需求进行修改。