stm32f407双can通讯源码

STM32F407是一款高性能的32位微控制器，集成了多个外设，可广泛应用于工业控制、机器人、汽车电子等领域。其中，双CAN通讯模块是STM32F407的重要特性之一，可实现单片机与其他设备之间的高速双向数据传输。

为了实现STM32F407双CAN通讯，需要首先了解CAN协议的基本知识和STM32F407的CAN外设的寄存器配置方法，然后编写相应的源码。以下是一个简单的STM32F407双CAN通讯的源码：

#include "stm32f4xx.h"
#include "stm32f4xx_can.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_gpio.h"

#define CANx                       CAN1
#define CAN_CLK                    RCC_APB1Periph_CAN1
#define CAN_RX_GPIO_CLK            RCC_AHB1Periph_GPIOA
#define CAN_RX_PIN                 GPIO_Pin_11
#define CAN_RX_GPIO_PORT           GPIOA
#define CAN_RX_SOURCE              GPIO_PinSource11
#define CAN_RX_AF                  GPIO_AF_CAN1
#define CAN_TX_GPIO_CLK            RCC_AHB1Periph_GPIOA
#define CAN_TX_PIN                 GPIO_Pin_12
#define CAN_TX_GPIO_PORT           GPIOA
#define CAN_TX_SOURCE              GPIO_PinSource12
#define CAN_TX_AF                  GPIO_AF_CAN1

CanTxMsg TxMessage;
CanRxMsg RxMessage;

void CAN_Config(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;
  CAN_InitTypeDef        CAN_InitStructure;
  CAN_FilterInitTypeDef  CAN_FilterInitStructure;

  RCC_AHB1PeriphClockCmd(CAN_RX_GPIO_CLK | CAN_TX_GPIO_CLK, ENABLE);

  RCC_APB1PeriphClockCmd(CAN_CLK, ENABLE);
  
  GPIO_PinAFConfig(CAN_RX_GPIO_PORT, CAN_RX_SOURCE, CAN_RX_AF);
  GPIO_PinAFConfig(CAN_TX_GPIO_PORT, CAN_TX_SOURCE, CAN_TX_AF);

  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStructure.GPIO_Pin = CAN_RX_PIN;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(CAN_RX_GPIO_PORT, &GPIO_InitStructure);

  GPIO_InitStructure.GPIO_Pin = CAN_TX_PIN;
  GPIO_Init(CAN_TX_GPIO_PORT, &GPIO_InitStructure);

  CAN_DeInit(CANx);

  CAN_InitStructure.CAN_TTCM = DISABLE;
  CAN_InitStructure.CAN_ABOM = DISABLE;
  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_12tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_3tq;
  CAN_InitStructure.CAN_Prescaler = 2;
  CAN_Init(CANx, &CAN_InitStructure);

  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_FilterNumber = 0;
  CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;
  CAN_FilterInit(&CAN_FilterInitStructure);
}

void CAN_Write(uint32_t id, uint8_t* data, uint8_t len)
{
  int i = 0;
  TxMessage.StdId = id;
  TxMessage.RTR = CAN_RTR_DATA;
  TxMessage.IDE = CAN_ID_STD;
  TxMessage.DLC = len;
  for (i = 0; i < len; i++)
  {
    TxMessage.Data[i] = data[i];
  }
  CAN_Transmit(CANx, &TxMessage);
}

uint8_t CAN_Read(uint32_t* id, uint8_t* data)
{
  if (CAN_MessagePending(CANx, CAN_FIFO0) == 0)
  {
    return 0;
  }
  CAN_Receive(CANx, CAN_FIFO0, &RxMessage);

  *id = RxMessage.StdId;
  int len = RxMessage.DLC > 8 ? 8 : RxMessage.DLC;

  int i;
  for (i = 0; i < len; i++)
  {
    data[i] = RxMessage.Data[i];
  }
  return len;
}

int main(void)
{
  CAN_Config();

  while (1)
  {
      uint8_t data[8] = {0xCD, 0x12, 0x34, 0xEF};
      CAN_Write(0x123, data, 4);
      delay(10);
  }
}

以上代码实现了STM32F407的双CAN通讯功能，其中CAN配置函数CAN_Config() 对CAN进行初始化和寄存器配置。CAN写函数CAN_Write() 和CAN读函数CAN_Read() 支持发送和接收CAN信息。在主函数中，通过给定ID和数据，连续发送CAN数据，可以实现双向通讯。

需要注意的是，以上代码仅供参考，实际开发时需要根据具体应用场景进行修改和优化。