[嵌入式]用STM32 中的 I2C读写EEPROM 实验工程讲解(三)

一、STM32CubeMx配置

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二、12C 的板级支持包

1、变量定义

#define  DATA_Size			256
#define  EEP_Firstpage      0x00
uint8_t I2c_Buf_Write[DATA_Size];
uint8_t I2c_Buf_Read[DATA_Size];

2.测试函数

uint8_t I2C_Test(void)
{
	uint16_t i;

	EEPROM_INFO("写入的数据");

	for ( i=0; i<DATA_Size; i++ ) //填充缓冲
	{   
		I2c_Buf_Write[i] =i;
		printf("0x%02X ", I2c_Buf_Write[i]);
		if(i%16 == 15)    
		printf("\n\r");    
	}

	//将I2c_Buf_Write中顺序递增的数据写入EERPOM中 
	I2C_EE_BufferWrite( I2c_Buf_Write, EEP_Firstpage, DATA_Size);

	EEPROM_INFO("读出的数据");
	//将EEPROM读出数据顺序保持到I2c_Buf_Read中
	I2C_EE_BufferRead(I2c_Buf_Read, EEP_Firstpage, DATA_Size); 
	//将I2c_Buf_Read中的数据通过串口打印
	for (i=0; i<DATA_Size; i++)
	{	
		if(I2c_Buf_Read[i] != I2c_Buf_Write[i])
		{
			printf("0x%02X ", I2c_Buf_Read[i]);
			EEPROM_ERROR("错误:I2C EEPROM写入与读出的数据不一致");
			return 0;
		}
		printf("0x%02X ", I2c_Buf_Read[i]);
		if(i%16 == 15)    
		printf("\n\r");

	}
	EEPROM_INFO("I2C(AT24C02)读写测试成功");
	return 1;
}

3. 换页（对EEPROM的写入主要是解决数据分页）

/**
  * @brief   将缓冲区中的数据写到I2C EEPROM中
  * @param   
  *		@arg pBuffer:缓冲区指针
  *		@arg WriteAddr:写地址
  *     @arg NumByteToWrite:写的字节数
  * @retval  无
  */
void I2C_EE_BufferWrite(uint8_t* pBuffer, uint8_t WriteAddr, uint16_t NumByteToWrite)
{
  uint8_t NumOfPage = 0, NumOfSingle = 0, Addr = 0, count = 0;

  Addr = WriteAddr % EEPROM_PAGESIZE;
  count = EEPROM_PAGESIZE - Addr;
  NumOfPage =  NumByteToWrite / EEPROM_PAGESIZE;
  NumOfSingle = NumByteToWrite % EEPROM_PAGESIZE;
 
  /* If WriteAddr is I2C_PageSize aligned  */
  if(Addr == 0) 
  {
    /* If NumByteToWrite < I2C_PageSize */
    if(NumOfPage == 0) 
    {
      I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
    }
    /* If NumByteToWrite > I2C_PageSize */
    else  
    {
      while(NumOfPage--)
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, EEPROM_PAGESIZE); 
        WriteAddr +=  EEPROM_PAGESIZE;
        pBuffer += EEPROM_PAGESIZE;
      }

      if(NumOfSingle!=0)
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
      }
    }
  }
  /* If WriteAddr is not I2C_PageSize aligned  */
  else 
  {
    /* If NumByteToWrite < I2C_PageSize */
    if(NumOfPage== 0) 
    {
      I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
    }
    /* If NumByteToWrite > I2C_PageSize */
    else
    {
      NumByteToWrite -= count;
      NumOfPage =  NumByteToWrite / EEPROM_PAGESIZE;
      NumOfSingle = NumByteToWrite % EEPROM_PAGESIZE;	
      
      if(count != 0)
      {  
        I2C_EE_PageWrite(pBuffer, WriteAddr, count);
        WriteAddr += count;
        pBuffer += count;
      } 
      
      while(NumOfPage--)
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, EEPROM_PAGESIZE);
        WriteAddr +=  EEPROM_PAGESIZE;
        pBuffer += EEPROM_PAGESIZE;  
      }
      if(NumOfSingle != 0)
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle); 
      }
    }
  }  
}

4.传入对应参数，读取函数

/**
  * @brief   从EEPROM里面读取一块数据 
  * @param   
  *		@arg pBuffer:存放从EEPROM读取的数据的缓冲区指针
  *		@arg WriteAddr:接收数据的EEPROM的地址
  *     @arg NumByteToWrite:要从EEPROM读取的字节数
  * @retval  无
  */
uint32_t I2C_EE_BufferRead(uint8_t* pBuffer, uint8_t ReadAddr, uint16_t NumByteToRead)
{
	HAL_StatusTypeDef status = HAL_OK;
	
	status=HAL_I2C_Mem_Read(&I2C_Handle,EEPROM_ADDRESS,ReadAddr, I2C_MEMADD_SIZE_8BIT, (uint8_t *)pBuffer, NumByteToRead,1000);

	return status;
}

5.读取函数解析

?6. i2c 流程

?7.读/写的数据格式

?8. 芯片引脚功能

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注：本案例参考野火hal库开发教程所记录的复习笔记