i2c.c

pic18系列单片机与24xxx系列的EEROM用I2C读写的库函数

#include <p18f452.h>
#include <i2c.h>
#include "991.h"

/************************************************************************
*     Function Name:    LDByteWriteI2C                                  *
*     Parameters:       EE memory ControlByte, address and data         *
*     Description:      Writes data one byte at a time to I2C EE        *
*                       device. This routine can be used for any I2C    *
*                       EE memory device, which only uses 1 byte of     *
*                       address data as in the 24LC01B/02B/04B/08B/16B. *
*                                                                       *
************************************************************************/

unsigned char LDByteWriteI2C( unsigned char ControlByte, unsigned char LowAdd, unsigned char data )
{
  IdleI2C();                          // ensure module is idle
  StartI2C();                         // initiate START condition
  while ( SSPCON2bits.SEN );          // wait until start condition is over 
  WriteI2C( ControlByte );            // write 1 byte - R/W bit should be 0
  IdleI2C();                          // ensure module is idle
  WriteI2C( LowAdd );                 // write address byte to EEPROM
  IdleI2C();                          // ensure module is idle
  WriteI2C ( data );                  // Write data byte to EEPROM
  IdleI2C();                          // ensure module is idle
  StopI2C();                          // send STOP condition
  while ( SSPCON2bits.PEN );          // wait until stop condition is over 
  while (EEAckPolling(ControlByte));  //Wait for write cycle to complete
  return ( 0 );                       // return with no error
}

/********************************************************************
*     Function Name:    LDByteReadI2C                               *
*     Parameters:       EE memory ControlByte, address, pointer and *
*                       length bytes.                               *
*     Description:      Reads data string from I2C EE memory        *
*                       device. This routine can be used for any I2C*
*                       EE memory device, which only uses 1 byte of *
*                       address data as in the 24LC01B/02B/04B/08B. *
*                                                                   *  
********************************************************************/

unsigned char LDByteReadI2C( unsigned char ControlByte, unsigned char address, unsigned char *data, unsigned char length )
{
  IdleI2C();                      // ensure module is idle
  StartI2C();                     // initiate START condition
  while ( SSPCON2bits.SEN );      // wait until start condition is over 
  WriteI2C( ControlByte );        // write 1 byte 
  IdleI2C();                      // ensure module is idle
  WriteI2C( address );            // WRITE word address to EEPROM
  IdleI2C();                      // ensure module is idle
  RestartI2C();                   // generate I2C bus restart condition
  while ( SSPCON2bits.RSEN );     // wait until re-start condition is over 
  WriteI2C( ControlByte | 0x01 ); // WRITE 1 byte - R/W bit should be 1 for read
  IdleI2C();                      // ensure module is idle
  getsI2C( data, length );       // read in multiple bytes
  NotAckI2C();                    // send not ACK condition
  while ( SSPCON2bits.ACKEN );    // wait until ACK sequence is over 
  StopI2C();                      // send STOP condition
  while ( SSPCON2bits.PEN );      // wait until stop condition is over 
  return ( 0 );                   // return with no error
}

/********************************************************************
*     Function Name:    LDPageWriteI2C                              *
*     Parameters:       EE memory ControlByte, address and pointer  *
*     Description:      Writes data string to I2C EE memory         *
*                       device. This routine can be used for any I2C*
*                       EE memory device, which uses 2 bytes of     *
*                       address data as in the 24LC32A/64/128/256.  *
*                                                                   *  
********************************************************************/

unsigned char LDPageWriteI2C( unsigned char ControlByte, unsigned char LowAdd, unsigned char *wrptr )
{
  IdleI2C();                      // ensure module is idle
  StartI2C();                     // initiate START condition
  while ( SSPCON2bits.SEN );      // wait until start condition is over 
  WriteI2C( ControlByte );        // write 1 byte - R/W bit should be 0
  IdleI2C();                      // ensure module is idle
  WriteI2C( LowAdd );             // write LowAdd byte to EEPROM
  IdleI2C();                      // ensure module is idle
  putstringI2C ( wrptr );         // pointer to data for page write
  IdleI2C();                      // ensure module is idle
  StopI2C();                      // send STOP condition
  while ( SSPCON2bits.PEN );      // wait until stop condition is over 
  return ( 0 );                   // return with no error
}

/********************************************************************
*     Function Name:    LDSequentialReadI2C                         *
*     Parameters:       EE memory ControlByte, address, pointer and *
*                       length bytes.                               *
*     Description:      Reads data string from I2C EE memory        *
*                       device. This routine can be used for any I2C*
*                       EE memory device, which only uses 1 byte of *
*                       address data as in the 24LC01B/02B/04B/08B. *
*                                                                   *  
********************************************************************/

unsigned char LDSequentialReadI2C( unsigned char ControlByte, unsigned char address, unsigned char *rdptr, unsigned char length )
{
  IdleI2C();                      // ensure module is idle
  StartI2C();                     // initiate START condition
  while ( SSPCON2bits.SEN );      // wait until start condition is over 
  WriteI2C( ControlByte );        // write 1 byte 
  IdleI2C();                      // ensure module is idle
  WriteI2C( address );            // WRITE word address to EEPROM
  IdleI2C();                      // ensure module is idle
  RestartI2C();                   // generate I2C bus restart condition
  while ( SSPCON2bits.RSEN );     // wait until re-start condition is over 
  WriteI2C( ControlByte | 0x01 ); // WRITE 1 byte - R/W bit should be 1 for read
  IdleI2C();                      // ensure module is idle
  getsI2C( rdptr, length );       // read in multiple bytes
  NotAckI2C();                    // send not ACK condition
  while ( SSPCON2bits.ACKEN );    // wait until ACK sequence is over 
  StopI2C();                      // send STOP condition
  while ( SSPCON2bits.PEN );      // wait until stop condition is over 
  return ( 0 );                   // return with no error
}

/************************************************************************
*     Function Name:    HDByteWriteI2C                                  *   
*     Parameters:       EE memory ControlByte, address and data         *
*     Description:      Writes data one byte at a time to I2C EE        *
*                       device. This routine can be used for any I2C    *
*                       EE memory device, which only uses 1 byte of     *
*                       address data as in the 24LC01B/02B/04B/08B/16B. *
*                                                                       *     
************************************************************************/

unsigned char HDByteWriteI2C( unsigned char ControlByte, unsigned char HighAdd, unsigned char LowAdd, unsigned char data )
{
  IdleI2C();                      // ensure module is idle
  StartI2C();                     // initiate START condition
  while ( SSPCON2bits.SEN );      // wait until start condition is over 
  WriteI2C( ControlByte );        // write 1 byte - R/W bit should be 0
  IdleI2C();                      // ensure module is idle
  WriteI2C( HighAdd );            // write address byte to EEPROM
  IdleI2C();                      // ensure module is idle
  WriteI2C( LowAdd );             // write address byte to EEPROM
  IdleI2C();                      // ensure module is idle
  WriteI2C ( data );              // Write data byte to EEPROM
  IdleI2C();                      // ensure module is idle
  StopI2C();                      // send STOP condition
  while ( SSPCON2bits.PEN );      // wait until stop condition is over 
  while (EEAckPolling(ControlByte));  //Wait for write cycle to complete
  return ( 0 );                   // return with no error
}