CAN通信配置代码

CAN通信配置代码主要涉及到硬件配置和软件配置两部分。

硬件配置：

1. 确定CAN总线的波特率和传输速率。

2. 配置CAN控制器的工作模式，如初始化CAN控制器和设置CAN控制器的工作模式。

3. 配置CAN总线的电气特性，如电缆阻抗匹配和终端电阻的配置。

4. 配置CAN控制器的过滤器，以过滤CAN总线上的消息。

软件配置：

1. 初始化CAN控制器并开启CAN总线。

2. 发送CAN消息：配置CAN数据帧的ID、数据、长度和格式，并将其发送到CAN总线上。

3. 接收CAN消息：配置CAN控制器的过滤器以过滤CAN总线上的消息，并读取接收到的CAN消息。

下面是一个STM32F4的CAN通信配置代码示例：

#include "stm32f4xx.h"
#include "stm32f4xx_can.h"

CAN_InitTypeDef CAN_InitStructure;
CAN_FilterInitTypeDef CAN_FilterInitStructure;

void CAN_Config(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;

  // 打开GPIO时钟
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

  // 打开CAN时钟
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

  // 配置GPIO引脚
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
  GPIO_Init(GPIOB, &GPIO_InitStructure);

  // 配置GPIO复用功能
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource8, GPIO_AF_CAN1);
  GPIO_PinAFConfig(GPIOB, GPIO_PinSource9, GPIO_AF_CAN1);

  // 配置CAN控制器
  CAN_InitStructure.CAN_TTCM = DISABLE;
  CAN_InitStructure.CAN_ABOM = ENABLE;
  CAN_InitStructure.CAN_AWUM = DISABLE;
  CAN_InitStructure.CAN_NART = DISABLE;
  CAN_InitStructure.CAN_RFLM = DISABLE;
  CAN_InitStructure.CAN_TXFP = DISABLE;
  CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;
  CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;
  CAN_InitStructure.CAN_BS1 = CAN_BS1_8tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_7tq;
  CAN_InitStructure.CAN_Prescaler = 4;
  CAN_Init(CAN1, &CAN_InitStructure);

  // 配置CAN过滤器
  CAN_FilterInitStructure.CAN_FilterNumber = 0;
  CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterIdHigh = 0x0000;
  CAN_FilterInitStructure.CAN_FilterIdLow = 0x0000;
  CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0x0000;
  CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0x0000;
  CAN_FilterInitStructure.CAN_FilterFIFOAssignment = 0;
  CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;
  CAN_FilterInit(&CAN_FilterInitStructure);

  // 启动CAN控制器
  CAN_ITConfig(CAN1, CAN_IT_FMP0, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_TME, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_ERR, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_EWG, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_EPV, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_BOF, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_LEC, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_ERR, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_WKU, ENABLE);
  CAN_ITConfig(CAN1, CAN_IT_SLK, ENABLE);
}