stm32f103编码器例程

以下是一个使用STM32F103芯片的编码器例程：

#include "stm32f10x.h"

#define ENCODER_TIM_PERIOD 0xFFFF
#define ENCODER_RESOLUTION 4096

volatile uint16_t encoderCount = 0;

void TIM2_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
    {
        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
        encoderCount++;
    }
}

void TIM3_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET)
    {
        TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
        encoderCount--;
    }
}

int main(void)
{
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2 | RCC_APB1Periph_TIM3, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    
    GPIO_InitTypeDef GPIO_InitStruct;
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStruct);
    
    TIM_TimeBaseInitTypeDef TIM_InitStruct;
    TIM_InitStruct.TIM_Period = ENCODER_TIM_PERIOD;
    TIM_InitStruct.TIM_Prescaler = 0;
    TIM_InitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_InitStruct.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM2, &TIM_InitStruct);
    TIM_TimeBaseInit(TIM3, &TIM_InitStruct);
    
    TIM_EncoderInterfaceConfig(TIM2, TIM_EncoderMode_TI12, TIM_ICPolarity_Rising, TIM_ICPolarity_Rising);
    TIM_EncoderInterfaceConfig(TIM3, TIM_EncoderMode_TI12, TIM_ICPolarity_Rising, TIM_ICPolarity_Rising);
    
    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);
    
    NVIC_InitTypeDef NVIC_InitStruct;
    NVIC_InitStruct.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStruct.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStruct);
    
    NVIC_InitStruct.NVIC_IRQChannel = TIM3_IRQn;
    NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStruct.NVIC_IRQChannelSubPriority = 1;
    NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStruct);
    
    TIM_Cmd(TIM2, ENABLE);
    TIM_Cmd(TIM3, ENABLE);
    
    while (1)
    {
        // 读取编码器计数器的值
        int16_t count = encoderCount;
        
        // 计算编码器的旋转角度
        float angle = (float) count / ENCODER_RESOLUTION * 360;
        
        // 处理旋转角度的值
        // ...
    }
}

该例程使用了STM32F103芯片的TIM2和TIM3定时器作为编码器的输入接口，通过中断的方式实现编码器计数器的读取。

在GPIO初始化部分，将PA0和PA1引脚配置为浮空输入模式。在定时器初始化部分，将TIM2和TIM3定时器的计数模式设置为上升计数模式，并且将编码器接口配置为TI12模式。

在中断处理函数中，当定时器溢出时，编码器计数器加1或减1。

在主循环中，读取编码器计数器的值，并计算出编码器的旋转角度。最后，对旋转角度的值进行处理。