请给我一份完整的使用n20电机控制四个麦克纳姆轮代码

由于代码的具体实现可能因硬件平台和机器人设计的不同而有所不同，这里提供的是一个示例代码，您可以根据自己的需要进行修改和优化。

#include <stdio.h>
#include <stdlib.h>
#include "stm32f10x.h"

// 电机控制引脚定义
#define MOTOR1_PWM_PIN GPIO_Pin_1
#define MOTOR1_DIR_PIN GPIO_Pin_2
#define MOTOR2_PWM_PIN GPIO_Pin_3
#define MOTOR2_DIR_PIN GPIO_Pin_4
#define MOTOR3_PWM_PIN GPIO_Pin_5
#define MOTOR3_DIR_PIN GPIO_Pin_6
#define MOTOR4_PWM_PIN GPIO_Pin_7
#define MOTOR4_DIR_PIN GPIO_Pin_8

// 电机最大速度
#define MAX_SPEED 1000.0

// 机器人速度结构体定义
typedef struct {
  float x; // x方向速度
  float y; // y方向速度
  float r; // 旋转速度
} RobotVelocity;

// 初始化GPIO
void Init_GPIO(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;

  // 启用GPIOA和GPIOB时钟
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE);

  // 配置MOTOR1控制引脚
  GPIO_InitStructure.GPIO_Pin = MOTOR1_PWM_PIN | MOTOR1_DIR_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  // 配置MOTOR2控制引脚
  GPIO_InitStructure.GPIO_Pin = MOTOR2_PWM_PIN | MOTOR2_DIR_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  // 配置MOTOR3控制引脚
  GPIO_InitStructure.GPIO_Pin = MOTOR3_PWM_PIN | MOTOR3_DIR_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  // 配置MOTOR4控制引脚
  GPIO_InitStructure.GPIO_Pin = MOTOR4_PWM_PIN | MOTOR4_DIR_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIOB, &GPIO_InitStructure);
}

// 初始化PWM
void Init_PWM(void)
{
  TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
  TIM_OCInitTypeDef TIM_OCInitStructure;

  // 启用TIM2时钟
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

  // 初始化TIM2
  TIM_TimeBaseStructure.TIM_Period = 1000;
  TIM_TimeBaseStructure.TIM_Prescaler = 72 - 1;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

  // 配置PWM输出
  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;

  // 配置MOTOR1 PWM输出
  TIM_OC1Init(TIM2, &TIM_OCInitStructure);
  TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable);

  // 配置MOTOR2 PWM输出
  TIM_OC2Init(TIM2, &TIM_OCInitStructure);
  TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable);

  // 配置MOTOR3 PWM输出
  TIM_OC3Init(TIM2, &TIM_OCInitStructure);
  TIM_OC3PreloadConfig(TIM2, TIM_OCPreload_Enable);

  // 配置MOTOR4 PWM输出
  TIM_OC4Init(TIM2, &TIM_OCInitStructure);
  TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Enable);

  // 启动TIM2
  TIM_Cmd(TIM2, ENABLE);
}

// 控制MOTOR1电机
void Control_Motor1(float speed)
{
  if (speed >= 0) {
    GPIO_SetBits(GPIOA, MOTOR1_DIR_PIN); // 正转
    TIM_SetCompare1(TIM2, (int)(speed * 1000.0 / MAX_SPEED));
  } else {
    GPIO_ResetBits(GPIOA, MOTOR1_DIR_PIN); // 反转
    TIM_SetCompare1(TIM2, (int)(-speed * 1000.0 / MAX_SPEED));
  }
}

// 控制MOTOR2电机
void Control_Motor2(float speed)
{
  if (speed >= 0) {
    GPIO_SetBits(GPIOA, MOTOR2_DIR_PIN); // 正转
    TIM_SetCompare2(TIM2, (int)(speed * 1000.0 / MAX_SPEED));
  } else {
    GPIO_ResetBits(GPIOA, MOTOR2_DIR_PIN); // 反转
    TIM_SetCompare2(TIM2, (int)(-speed * 1000.0 / MAX_SPEED));
  }
}

// 控制MOTOR3电机
void Control_Motor3(float speed)
{
  if (speed >= 0) {
    GPIO_SetBits(GPIOB, MOTOR3_DIR_PIN); // 正转
    TIM_SetCompare3(TIM2, (int)(speed * 1000.0 / MAX_SPEED));
  } else {
    GPIO_ResetBits(GPIOB, MOTOR3_DIR_PIN); // 反转
    TIM_SetCompare3(TIM2, (int)(-speed * 1000.0 / MAX_SPEED));
  }
}

// 控制MOTOR4电机
void Control_Motor4(float speed)
{
  if (speed >= 0) {
    GPIO_SetBits(GPIOB, MOTOR4_DIR_PIN); // 正转
    TIM_SetCompare4(TIM2, (int)(speed * 1000.0 / MAX_SPEED));
  } else {
    GPIO_ResetBits(GPIOB, MOTOR4_DIR_PIN); // 反转
    TIM_SetCompare4(TIM2, (int)(-speed * 1000.0 / MAX_SPEED));
  }
}

// 控制麦克纳姆轮机器人
void Control_Mecanum_Wheel(RobotVelocity velocity)
{
  float v1 = velocity.x + velocity.y + velocity.r;
  float v2 = velocity.x - velocity.y - velocity.r;
  float v3 = velocity.x - velocity.y + velocity.r;
  float v4 = velocity.x + velocity.y - velocity.r;

  Control_Motor1(v1);
  Control_Motor2(v2);
  Control_Motor3(v3);
  Control_Motor4(v4);
}

int main(void)
{
  Init_GPIO();
  Init_PWM();

  // 测试代码，使机器人向前移动
  RobotVelocity velocity = {100.0, 0.0, 0.0};
  Control_Mecanum_Wheel(velocity);

  while(1);

  return 0;
}

在这个示例代码中，使用PWM信号控制四个N20电机，实现了控制麦克纳姆轮机器人的功能。需要注意的是，具体的代码实现可能会因为硬件平台和机器人设计的不同而有所不同。