写一个用stm32f103c8t6通过PID控制PWM调节直流电机速度的代码

当然可以！以下是一个基于STM32F103C8T6使用PID控制PWM调节直流电机速度的示例代码：

#include "stm32f10x.h"

#define PWM_MAX 1000 // PWM的最大值
#define TARGET_SPEED 500 // 目标速度
#define KP 0.5 // 比例系数
#define KI 0.2 // 积分系数
#define KD 0.1 // 微分系数

uint16_t current_speed = 0; // 当前速度
uint16_t pwm_value = 0; // PWM的值

float error = 0; // 误差
float previous_error = 0; // 上一次的误差
float integral = 0; // 积分
float derivative = 0; // 微分

void TIM3_PWM_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    TIM_TimeBaseStructure.TIM_Period = 1000 - 1;
    TIM_TimeBaseStructure.TIM_Prescaler = 72 - 1;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);

    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_Pulse = 0;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC2Init(TIM3, &TIM_OCInitStructure);

    TIM_Cmd(TIM3, ENABLE);
}

void TIM2_Encoder_Init(void)
{
    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_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    TIM_EncoderInterfaceConfig(TIM2, TIM_EncoderMode_TI12, TIM_ICPolarity_Rising, TIM_ICPolarity_Rising);
    TIM_ICStructInit(&TIM_ICInitStructure);
    TIM_ICInitStructure.TIM_ICFilter = 10;
    TIM_ICInit(TIM2, &TIM_ICInitStructure);

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

    TIM_Cmd(TIM2, ENABLE);
}

void PID_Controller(void)
{
    error = TARGET_SPEED - current_speed;
    integral += error;
    derivative = error - previous_error;

    pwm_value = KP * error + KI * integral + KD * derivative;

    if (pwm_value > PWM_MAX)
        pwm_value = PWM_MAX;
    else if (pwm_value < 0)
        pwm_value = 0;

    previous_error = error;
}

int main(void)
{
    // 初始化PWM
    TIM3_PWM_Init();
    // 初始化编码器
    TIM2_Encoder_Init();

    while (1)
    {
        // 获取当前速度
        current_speed = TIM2->CNT;

        // PID控制
        PID_Controller();

        // 设置PWM值
        TIM3->CCR2 = pwm_value;
    }
}

请注意，以上代码仅为示例代码，可能需要根据你的具体需求进行修改。还需要确保你已正确配置了STM32的时钟和引脚等相关设置。