帮我写关于stm32如何通过霍尔编码器计算直流电机旋转的圈数的实例代码

好的，以下是关于STM32如何通过霍尔编码器计算直流电机旋转的圈数的实例代码：

#include "stm32f4xx.h"

#define HALL_A_PIN GPIO_Pin_0
#define HALL_B_PIN GPIO_Pin_1
#define HALL_C_PIN GPIO_Pin_2

#define HALL_A_PORT GPIOA
#define HALL_B_PORT GPIOA
#define HALL_C_PORT GPIOA

#define HALL_TIM TIM2

volatile uint32_t hall_count = 0;

void HALL_TIM_IRQHandler(void)
{
    if (TIM_GetITStatus(HALL_TIM, TIM_IT_CC1) != RESET)
    {
        TIM_ClearITPendingBit(HALL_TIM, TIM_IT_CC1);
        if (GPIO_ReadInputDataBit(HALL_A_PORT, HALL_A_PIN) == GPIO_ReadInputDataBit(HALL_B_PORT, HALL_B_PIN))
        {
            hall_count++;
        }
        else
        {
            hall_count--;
        }
    }
}

void HALL_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_ICInitTypeDef TIM_ICInitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

    GPIO_InitStructure.GPIO_Pin = HALL_A_PIN | HALL_B_PIN | HALL_C_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    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(HALL_TIM, &TIM_ICInitStructure);

    TIM_ClearITPendingBit(HALL_TIM, TIM_IT_CC1);
    TIM_ITConfig(HALL_TIM, TIM_IT_CC1, 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);

    TIM_Cmd(HALL_TIM, ENABLE);
}

int main(void)
{
    HALL_Init();

    while (1)
    {
        // do something
    }
}

这段代码使用了STM32的TIM2定时器和GPIO模块，通过读取霍尔编码器的A、B两个信号来计算直流电机的旋转圈数。在中断处理函数中，根据A、B两个信号的状态变化来判断电机的旋转方向，并更新计数器的值。在主函数中，可以根据计数器的值来获取电机的旋转圈数。