STM32如何利用编码器测距代码

可以使用STM32的定时器和外部中断来实现编码器测距。以下是一个简单的示例代码：

#include "stm32f10x.h"

int main(void)
{
    // 初始化GPIO口和定时器
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_ICInitTypeDef TIM_ICInitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    GPIO_PinRemapConfig(GPIO_PartialRemap_TIM2, ENABLE);

    TIM_TimeBaseStructure.TIM_Period = 65535;
    TIM_TimeBaseStructure.TIM_Prescaler = 0;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

    TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
    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 = 0x0;
    TIM_ICInit(TIM2, &TIM_ICInitStructure);

    TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
    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 = 0x0;
    TIM_ICInit(TIM2, &TIM_ICInitStructure);

    TIM_Cmd(TIM2, ENABLE);

    // 等待编码器开始运行
    while (!GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_0))
        ;

    // 计算距离
    uint16_t last_count = 0;
    uint16_t current_count = 0;
    while (1)
    {
        current_count = TIM_GetCounter(TIM2);
        if (current_count < last_count)
        {
            // 计算距离
            uint16_t distance = current_count + (65535 - last_count);
            // 处理距离数据
            // ...
        }
        last_count = current_count;
    }
}

在这个代码中，我们初始化了GPIO口和定时器，并使用定时器的输入捕获模式来读取编码器的脉冲。我们使用中断来计算距离，并在主循环中不断地读取编码器数据。注意，我们需要等待编码器开始运行，才能开始计算距离。