24c256.c

24c256的底层驱动

/****************************************************************
 *	CopyRight  Reserved:  MR QIU  
 *	文件名：24c256.c
 *	描述:提供24c256的底层驱动。
 *
 *	版本：v1.0
 *	作者：ktop
 *	日期：2004/12/31
****************************************************************/
#define		_24C256_C
#include "24C256.h"
#include "stm32f10x_it.h"

/**************************************************************
* Name:I2C_EE_PageWrite
*  input:u8* pBuffer, u8 WriteAddr, u8 NumByteToWrite 
*  output:none
*
***************************************************************/
void I2C_EE_BufferWrite(u8* pBuffer, u16 WriteAddr, u8 NumByteToWrite)
{
  /* Send START condition */
  I2C_GenerateSTART(I2C_EPROM, ENABLE);
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_MODE_SELECT)); 
  
  /* Send EEPROM address for write */
   I2C_Send7bitAddress(I2C_EPROM,EPROM_ADDR, I2C_Direction_Transmitter);

  /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));  

  /* Send the EEPROM's internal address  to write to */    
  I2C_SendData(I2C_EPROM, WriteAddr>>8);  

  /* Test on EV8 and clear it */
  while(! I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
 
   /* Send the EEPROM's internal address  to write to */    
  I2C_SendData(I2C_EPROM, WriteAddr&0x00ff);  

  /* Test on EV8 and clear it */
  while(! I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
 

  /* While there is data to be written */
  while(NumByteToWrite--)  
  {
    /* Send the current byte */
    I2C_SendData(I2C_EPROM, *pBuffer); 

    /* Point to the next byte to be written */
    pBuffer++; 
  
    /* Test on EV8 and clear it */
    while (!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  }

  /* Send STOP condition */
  I2C_GenerateSTOP(I2C_EPROM, ENABLE);
}

/***********************************************************************
*  	Name: 	2C_EE_BufferRead
*  	Input:	pBuffer read to it,ReadAddr  read address,NumByteToRead the 
*			number of ready to read
*  	Output: None
***********************************************************************/
void I2C_EE_BufferRead(u8* pBuffer, u16 ReadAddr, u8 NumByteToRead)
{  
  /* Send START condition */
  I2C_GenerateSTART(I2C_EPROM, ENABLE);
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_MODE_SELECT));
  
  /* In the case of a single data transfer disable ACK before reading the data */
  if(NumByteToRead==1) 
  {
    I2C_AcknowledgeConfig(I2C_EPROM, DISABLE);
  }
  
  /* Send EEPROM address for write */
  I2C_Send7bitAddress(I2C_EPROM,EPROM_ADDR, I2C_Direction_Transmitter);

  /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
  
  /* Clear EV6 by setting again the PE bit */
  I2C_Cmd(I2C_EPROM, ENABLE);

  /* Send the EEPROM's internal address  to write to (heigh)*/
  I2C_SendData(I2C_EPROM, ReadAddr>>8);  

  /* Test on EV8 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  
  /* Send the EEPROM's internal address  to write to (heigh)*/
  I2C_SendData(I2C_EPROM, ReadAddr&0xff);  

  /* Test on EV8 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
  
  
  /* Send STRAT condition a second time */  
  I2C_GenerateSTART(I2C_EPROM, ENABLE);
  
  /* Test on EV5 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_MODE_SELECT));
  
  /* Send EEPROM address for read */
  I2C_Send7bitAddress(I2C_EPROM,EPROM_ADDR, I2C_Direction_Receiver);
  
  /* Test on EV6 and clear it */
  while(!I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED));
  
  /* While there is data to be read */
  while(NumByteToRead)  
  {
    /* Test on EV7 and clear it */
    if(I2C_CheckEvent(I2C_EPROM, I2C_EVENT_MASTER_BYTE_RECEIVED))  
    {
      if(NumByteToRead == 2)
      {
        /* Disable Acknowledgement */
        I2C_AcknowledgeConfig(I2C_EPROM, DISABLE);
      }

      if(NumByteToRead == 1)
      {
        /* Send STOP Condition */
        I2C_GenerateSTOP(I2C_EPROM, ENABLE);
      }
      
      /* Read a byte from the EEPROM */
      *pBuffer = I2C_ReceiveData(I2C_EPROM);

      /* 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(I2C_EPROM, ENABLE);
}