将 I2C 接口初始化用作从机和/或主机的代码

以下是使用STM32 HAL库将I2C接口初始化作为主机和/或从机的示例代码：

作为主机：

I2C_HandleTypeDef hi2c;

void MX_I2C_Init(void)
{
  hi2c.Instance = I2C1;
  hi2c.Init.ClockSpeed = 100000;
  hi2c.Init.DutyCycle = I2C_DUTYCYCLE_2;
  hi2c.Init.OwnAddress1 = 0;
  hi2c.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c.Init.OwnAddress2 = 0;
  hi2c.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;

  if (HAL_I2C_Init(&hi2c) != HAL_OK)
  {
    Error_Handler();
  }
}

void I2C_WriteData(uint8_t DevAddress, uint8_t MemAddress, uint8_t *pData, uint16_t Size)
{
  HAL_I2C_Mem_Write(&hi2c, DevAddress, MemAddress, I2C_MEMADD_SIZE_8BIT, pData, Size, 1000);
}

void I2C_ReadData(uint8_t DevAddress, uint8_t MemAddress, uint8_t *pData, uint16_t Size)
{
  HAL_I2C_Mem_Read(&hi2c, DevAddress, MemAddress, I2C_MEMADD_SIZE_8BIT, pData, Size, 1000);
}

作为从机：

I2C_HandleTypeDef hi2c;

void MX_I2C_Init(void)
{
  hi2c.Instance = I2C1;
  hi2c.Init.ClockSpeed = 100000;
  hi2c.Init.DutyCycle = I2C_DUTYCYCLE_2;
  hi2c.Init.OwnAddress1 = 0x50;   //设置从机地址为0x50
  hi2c.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c.Init.OwnAddress2 = 0;
  hi2c.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;

  if (HAL_I2C_Init(&hi2c) != HAL_OK)
  {
    Error_Handler();
  }

  HAL_I2C_EnableListen_IT(&hi2c);  //使能从机监听
}

void HAL_I2C_AddrCallback(I2C_HandleTypeDef *hi2c, uint8_t TransferDirection, uint16_t AddrMatchCode)
{
  if(TransferDirection == I2C_DIRECTION_RECEIVE)
  {
    //执行从机接收操作
  }
  else
  {
    //执行从机发送操作
  }
}

void HAL_I2C_SlaveTxCpltCallback(I2C_HandleTypeDef *hi2c)
{
  //从机发送完成回调函数
}

void HAL_I2C_SlaveRxCpltCallback(I2C_HandleTypeDef *hi2c)
{
  //从机接收完成回调函数
}

以上示例代码中，主机初始化了I2C1接口，并提供了写入和读取函数。从机同样初始化了I2C1接口，并设置了从机地址为0x50，同时注册了从机回调函数以接收和发送数据。需要注意的是，从机回调函数的实现需要根据具体应用场景来编写。