i2c_ee.c

LWIP在STM32裸机上的移植

/*这个文件将设置存储芯片信息，现在采用24C64芯片*/
#include "stm32f10x_i2c.h"
#include "i2c_ee.h"
#include <stdio.h>

#define I2C_Speed              400000     /*高速模式400K*/
#define I2C1_SLAVE_ADDRESS7    0xA0       /*器件从地址*/
#define I2C_PageSize           32          /*EEPROM页面大小为8bit*/

u16 EEPROM_ADDRESS;

void GPIO_Configuration(void);
void I2C_Configuration(void);

/*为I2C1配置所在的GPIO管脚*/
void GPIO_Configuration(void)
{
  
  GPIO_InitTypeDef  GPIO_InitStructure; 
  /*GPIOB和I2C1使用不同的时钟总线，即APB1和APB2*/
  GPIO_PinRemapConfig(GPIO_Remap_I2C1, ENABLE);
  
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1,ENABLE);
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);
    
  /*配置SCL和SDA管脚*/
  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_8 | GPIO_Pin_9;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;/*复用开漏输出*/
  GPIO_Init(GPIOB, &GPIO_InitStructure);
}

/*I2C功能配置*/
void I2C_Configuration(void)
{
  I2C_InitTypeDef  I2C_InitStructure; 

  I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;/*I2C接口为I2C模式*/
  I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;/*快速工作模式，Tlow/Thigh=2，占空比*/
  I2C_InitStructure.I2C_OwnAddress1 = I2C1_SLAVE_ADDRESS7;/*设备地址为从机地址，已经赋值*/
  I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;/*使能应答*/
  I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;/*应答7位地址*/
  I2C_InitStructure.I2C_ClockSpeed = I2C_Speed;/*时钟频率为400K*/
  
  /*使能I2C1外设*/
  I2C_Cmd(I2C1, ENABLE);
  
  I2C_Init(I2C1, &I2C_InitStructure);
  
  /*使能应答功能*/
  I2C_AcknowledgeConfig(I2C1, ENABLE);
    
  printf("\n\r I2C_Configuration----\r");
    
}

/*初始化I2C接口的EEPROM外设*/
void I2C_EE_Init()
{
  GPIO_Configuration();
  I2C_Configuration();
  
  /*根据芯片链接的管脚的不同，24C02有不同的地址，这里开发板上默认的是0XA0，
  如果不是，可以在i2c_ee.h中进行修改*/
  /*指定EEPROM的地址*/
  /*选在EEPROM的块0进行写操作*/
  EEPROM_ADDRESS = EEPROM_Block0_ADDRESS;
}

/*******************************************************************************
                          向EEPROM写入数据
* 输入参数         - pBuffer :指向包含要写入EEPROM的数据的缓冲区
*                  - WriteAddr :要写入数据的EEPROM的内部地址
*                  - NumByteToWrite :要写入的数据总byte
*******************************************************************************/
void I2C_EE_BufferWrite(u8* pBuffer, u8 WriteAddr, u16 NumByteToWrite)
{
  /*初始化（要写入的数据）页面、非整页的byte、地址、数据计数器为0*/
  u8 NumOfPage = 0, NumOfSingle = 0, Addr = 0, count = 0;

  Addr = WriteAddr % I2C_PageSize;/*这里求出满足整页面后还剩下的不足一页的地址*/
  count = I2C_PageSize - Addr;/*这里求出从那一页那个地址开始写*/
  NumOfPage =  NumByteToWrite / I2C_PageSize;/*写多少页*/
  NumOfSingle = NumByteToWrite % I2C_PageSize;/*单独剩下多少bit*/
 
  /*如果地址页对齐，即刚好整页面，255的整数倍*/
  if(Addr == 0) 
  {
    if(NumOfPage == 0) /*表示数据量《255*/
    {
      I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
      I2C_EE_WaitEepromStandbyState();/*等待EEPROM的准备状态*/
    }
    /*如果为页面大小255的整数倍（2倍及以上）*/
    else  
    {
      while(NumOfPage--)
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, I2C_PageSize); 
    	I2C_EE_WaitEepromStandbyState();
        WriteAddr +=  I2C_PageSize;
        pBuffer += I2C_PageSize;
      }

      if(NumOfSingle!=0)
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
        I2C_EE_WaitEepromStandbyState();
      }
    }
  }
  /*若写地址不是页对齐即不是255的整数倍*/
  else 
  {
    /*数据小于页面大小*/
    if(NumOfPage== 0) /*不够一页*/
    {
      I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle);
      I2C_EE_WaitEepromStandbyState();
    }
    /*数据大于一个页面*/
    else
    {
      NumByteToWrite -= count;/*字节计数*/
      NumOfPage =  NumByteToWrite / I2C_PageSize;/*写几页*/
      NumOfSingle = NumByteToWrite % I2C_PageSize;/*剩下几个单独字节*/	
      
      if(count != 0)/*数据没写完*/
      {  
        I2C_EE_PageWrite(pBuffer, WriteAddr, count);
        I2C_EE_WaitEepromStandbyState();
        WriteAddr += count;
        pBuffer += count;
      } 
      
      while(NumOfPage--)/*整页没写完*/
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, I2C_PageSize);
        I2C_EE_WaitEepromStandbyState();
        WriteAddr +=  I2C_PageSize;
        pBuffer += I2C_PageSize;  
      }
      if(NumOfSingle != 0)/*单独字节没写完*/
      {
        I2C_EE_PageWrite(pBuffer, WriteAddr, NumOfSingle); 
        I2C_EE_WaitEepromStandbyState();
      }
    }
  }  
}

/*******************************************************************************
                           写入一个字节8bit到EEPROM
* 函数描述             向EEPROM中写入一个byte
* 输入参数             pBuffer : 指向包含要写入EEPROM的数据的缓冲区
*                      WriteAddr : EEPROM的内部地址.
*******************************************************************************/
void I2C_EE_ByteWrite(u8* pBuffer, u8 WriteAddr)
{
  /*发送开始信号*/
  I2C_GenerateSTART(I2C1, ENABLE);
  /*检查最近一次I2C事件是否是输入的事件*/
  /* Test on EV5 and clear it EV5：选择主机模式*/
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));  

  /*发送7位从机地址，即EEPROM在I2C上的地址*/
  I2C_Send7bitAddress(I2C1, EEPROM_ADDRESS, I2C_Direction_Transmitter);
  
  /* Test on EV6 and clear it EV6：选择主机发送模式*/
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
      
  /*下面的三条语句为新加的，24C64的地址为16位，需要分成两次写入*/
  I2C_SendData(I2C1,(WriteAddr&0xff00)>>8);// 发送前8位地址 
  
  /* Test on EV8 and clear it EV8：主机8位字节已传送*/
  while(!I2C_CheckEvent(I2C1,I2C_EVENT_MASTER_BYTE_TRANSMITTED));  

  I2C_SendData(I2C1, (WriteAddr&0xff));// 发送后8位地址 

  /* 发送EEPROM的内部地址*/
  //I2C_SendData(I2C1, WriteAddr);
  
  /* Test on EV8 and clear it EV8：主机8位字节已传送*/
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));

  /*发送要写的数据*/
  I2C_SendData(I2C1, *pBuffer); 
   
  /* Test on EV8 and clear it EV8：主机8位字节已传送*/
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  
  /*发送停止位*/
  I2C_GenerateSTOP(I2C1, ENABLE);
}

/*******************************************************************************
                             连续写多个字节函数
* 函数描述         : 在一个单独的写周期内向EEPROM写入几个字节，字节个数不能大于页面大小
* 输入参数         : - pBuffer : 指向包含要写入EEPROM的数据的缓冲区
*                  - WriteAddr : EEPROM的内部地址
*                  - NumByteToWrite : 要写的字节个数，不能超过255
*******************************************************************************/
void I2C_EE_PageWrite(u8* pBuffer, u8 WriteAddr, u8 NumByteToWrite)
{
  /*测试总线忙标志位*/  
  while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY));
    
  /*发送开始条件*/
  I2C_GenerateSTART(I2C1, ENABLE);
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT)); 
  
  /*发送从机地址*/
  I2C_Send7bitAddress(I2C1, EEPROM_ADDRESS, I2C_Direction_Transmitter);
  
    /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
   /*新加的语句*/
  I2C_SendData(I2C1, (WriteAddr&0xff00)>>8);// 发送前8位地址 
   
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED)); //test on EV8 and clear it 

  I2C_SendData(I2C1, (WriteAddr&0xff));// 发送后8位地址 

  
  /* Test on EV6 and clear it */
  //while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));  

  /*发送EEPROM在要写入数据的内部地址*/    
  //I2C_SendData(I2C1, WriteAddr);  

  /* Test on EV8 and clear it */
  while(! I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));

  /*写入数据操作*/
  while(NumByteToWrite--)  
  {
    /*发送数据*/
    I2C_SendData(I2C1, *pBuffer); 

    /*指向下一个bit*/
    pBuffer++; 
  
    /* Test on EV8 and clear it */
    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  }

  /*发送停止位*/
  I2C_GenerateSTOP(I2C1, ENABLE);
}

/*******************************************************************************
                      从EEPROM中读取一个或者多个连续字节数据
* 函数描述            从EEPROM中读取一个或者多个连续字节数据
* 参数输入          : - pBuffer : 指向包含要写入EEPROM的数据的缓冲区
*                     - ReadAddr : 要读取数据的EEPROM的内部地址
*                     - NumByteToRead :要读取的数据总量
*******************************************************************************/
void I2C_EE_BufferRead(u8* pBuffer, u8 ReadAddr, u16 NumByteToRead)
{  
  //*((u8 *)0x4001080c) |=0x80; 
    while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY)); 
       
  /* Send START condition */
  I2C_GenerateSTART(I2C1, ENABLE);
  //*((u8 *)0x4001080c) &=~0x80;
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));

  /* Send EEPROM address for write */
  I2C_Send7bitAddress(I2C1, EEPROM_ADDRESS, I2C_Direction_Transmitter);

  /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
  
  /* Clear EV6 by setting again the PE bit */
  I2C_Cmd(I2C1, ENABLE);
  
  I2C_SendData(I2C1, (ReadAddr&0xff00)>>8);// 发送前8位地址 
   
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED)); //test on EV8 and clear it 

  I2C_SendData(I2C1, (ReadAddr&0xff));// 发送后8位地址

  /* Send the EEPROM's internal address to write to */
  //I2C_SendData(I2C1, ReadAddr);  

  /* Test on EV8 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  
  /* Send STRAT condition a second time */  
  I2C_GenerateSTART(I2C1, ENABLE);
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
  
  /* Send EEPROM address for read */
  I2C_Send7bitAddress(I2C1, EEPROM_ADDRESS, I2C_Direction_Receiver);
  
  /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
  
  /* While there is data to be read */
  while(NumByteToRead)  
  {
    if(NumByteToRead == 1)
    {
      /*失能应答*/
      I2C_AcknowledgeConfig(I2C1, DISABLE);
      
      /* Send STOP Condition */
      I2C_GenerateSTOP(I2C1, ENABLE);
    }

    /* Test on EV7 and clear it */
    if(I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED))  
    {      
      /* Read a byte from the EEPROM */
      *pBuffer = I2C_ReceiveData(I2C1);

      /* Point to the next location where the byte read will be saved */
      pBuffer++; 
      
      /* Decrement the read bytes counter */
      NumByteToRead--;        
    }   
  }

  /* Enable Acknowledgement to be ready for another reception */
  I2C_AcknowledgeConfig(I2C1, ENABLE);
}

/*等待EEPROM的准备状态*/
void I2C_EE_WaitEepromStandbyState(void)  /*等待EEPROM的准备态*/    
{
  vu16 SR1_Tmp = 0;

  do
  {
    /*发送开始条件*/
    I2C_GenerateSTART(I2C1, ENABLE);
    /*读取I2C1的状态寄存器1状态*/
    SR1_Tmp = I2C_ReadRegister(I2C1, I2C_Register_SR1);
    /*为写发送EEPROM写地址*/
    I2C_Send7bitAddress(I2C1, EEPROM_ADDRESS, I2C_Direction_Transmitter);
  }
  while(!(I2C_ReadRegister(I2C1, I2C_Register_SR1) & 0x0002));
  
  /*清应答错误标志位*/
  I2C_ClearFlag(I2C1, I2C_FLAG_AF);
    /*产生停止条件*/    
    I2C_GenerateSTOP(I2C1, ENABLE); 
}