STM32F407 巡线代码

以下是一个简单的STM32F407巡线代码的示例，使用了ADC模块读取巡线传感器的模拟信号，并通过PID算法计算出一个偏差值，再通过PWM控制电机来实现巡线：

#include "stm32f4xx.h"
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define ADC_RESOLUTION 4096         // ADC分辨率
#define SENSOR_NUM 8                // 巡线传感器数量
#define SENSOR_THRESHOLD 500        // 巡线传感器阈值
#define BASE_SPEED 500              // 基础速度
#define KP 0.8                      // 比例系数
#define KD 0.01                     // 微分系数
#define KI 0.0                      // 积分系数
#define PWM_FREQ 1000               // PWM频率
#define PWM_PERIOD (SystemCoreClock / PWM_FREQ)
#define PWM_MAX_DUTY (PWM_PERIOD - 1)

uint16_t adc_value[SENSOR_NUM];

int16_t error = 0;
int16_t last_error = 0;
int16_t integral = 0;
int16_t derivative = 0;

uint16_t left_motor_speed = 0;
uint16_t right_motor_speed = 0;

void ADC_Config(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    ADC_InitTypeDef ADC_InitStructure;
    DMA_InitTypeDef DMA_InitStructure;

    /* Enable GPIO clocks */
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

    /* Enable ADC clocks */
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);

    /* Enable DMA clocks */
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);

    /* Configure ADC pins */
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    /* Configure DMA */
    DMA_InitStructure.DMA_Channel = DMA_Channel_0;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) &ADC1->DR;
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t) &adc_value[0];
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    DMA_InitStructure.DMA_BufferSize = SENSOR_NUM;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
    DMA_InitStructure.DMA_Priority = DMA_Priority_High;
    DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
    DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
    DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    DMA_Init(DMA2_Stream0, &DMA_InitStructure);

    /* Enable DMA */
    DMA_Cmd(DMA2_Stream0, ENABLE);

    /* Configure ADC */
    ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
    ADC_InitStructure.ADC_ScanConvMode = ENABLE;
    ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
    ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
    ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_NbrOfConversion = SENSOR_NUM;
    ADC_Init(ADC1, &ADC_InitStructure);

    /* Configure ADC channels */
    ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_15Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_15Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 3, ADC_SampleTime_15Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 4, ADC_SampleTime_15Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_4, 5, ADC_SampleTime_15Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_5, 6, ADC_SampleTime_15Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_6, 7, ADC_SampleTime_15Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_7, 8, ADC_SampleTime_15Cycles);

    /* Enable ADC DMA */
    ADC_DMACmd(ADC1, ENABLE);

    /* Enable ADC */
    ADC_Cmd(ADC1, ENABLE);
}

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

    /* Enable GPIO clocks */
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

    /* Enable TIM clocks */
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);

    /* Configure PWM pins */
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    /* Connect PWM pins to TIM4 */
    GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_TIM4);
    GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_TIM4);

    /* Configure TIM4 base */
    TIM_TimeBaseStructure.TIM_Period = PWM_PERIOD;
    TIM_TimeBaseStructure.TIM_Prescaler = 0;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);

    /* Configure TIM4 channel 1 */
    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_OC1Init(TIM4, &TIM_OCInitStructure);

    /* Configure TIM4 channel 2 */
    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(TIM4, &TIM_OCInitStructure);

    /* Enable TIM4 */
    TIM_Cmd(TIM4, ENABLE);
}

void Motor_SetSpeed(uint16_t left_speed, uint16_t right_speed)
{
    TIM4->CCR1 = (left_speed > PWM_MAX_DUTY) ? PWM_MAX_DUTY : left_speed;
    TIM4->CCR2 = (right_speed > PWM_MAX_DUTY) ? PWM_MAX_DUTY : right_speed;
}

void PID_Control(void)
{
    uint16_t i;
    int16_t sum = 0;

    /* Calculate error */
    for (i = 0; i < SENSOR_NUM; i++) {
        if (adc_value[i] > SENSOR_THRESHOLD) {
            sum += (i - (SENSOR_NUM-1)/2) * (ADC_RESOLUTION - adc_value[i]);
        }
    }
    error = sum / 1000;

    /* Calculate integral */
    integral += error;

    /* Calculate derivative */
    derivative = error - last_error;
    last_error = error;

    /* Calculate motor speeds */
    left_motor_speed = BASE_SPEED + KP * error + KI * integral + KD * derivative;
    right_motor_speed = BASE_SPEED - KP * error - KI * integral - KD * derivative;

    /* Set motor speeds */
    Motor_SetSpeed(left_motor_speed, right_motor_speed);
}

int main(void)
{
    ADC_Config();
    PWM_Config();

    while (1) {
        PID_Control();
    }
}

在这个示例中，我们使用了DMA来持续读取ADC模块的值，并使用PID算法计算出一个偏差值。然后，我们通过PWM控制电机的速度来实现巡线。你需要根据你的具体硬件和传感器来调整代码，并进行适当的调试和优化。