eeprom.c

来自「LCDTV的source code,含周邊ic的driver code ,sca」· C语言 代码 · 共 137 行

/*******************************************************************************
  EEPROM.C
  Copyright (c) SmartASIC, Inc. All rights reserved.
*******************************************************************************/
#include <MTV230.H>
#define EE_MCU 0xA0                                                                                      
/*==============================================================================

==============================================================================*/
void IIC_Start(void) {

  MCU_SDA=1;
  MCU_SCL=1;
  MCU_SDA=0;
  MCU_SCL=0;

  }


/*==============================================================================

==============================================================================*/
void IIC_Stop(void) {

  MCU_SDA=0;
  MCU_SCL=1;
  MCU_SDA=1;

  }


/*==============================================================================

==============================================================================*/
bit IIC_Data_In(unsigned char bytedata) {

  unsigned char i;
  bit ack;

  for(i=0; i<8; i++) {
    MCU_SDA=bytedata&0x80;
    MCU_SCL=1;
    bytedata<<=1;
    MCU_SCL=0;
    }
  MCU_SDA=1;
  MCU_SCL=1;
  ack=MCU_SDA;
  MCU_SCL=0;
  MCU_SDA=0;

  return ack;

  }


/*==============================================================================

==============================================================================*/
unsigned char IIC_Data_Out(void) {

  unsigned char i, bytedata=0;

  MCU_SDA=1;
  for(i=0; i<8; i++) {
    MCU_SCL=1;
    bytedata<<=1;
    bytedata|=MCU_SDA;
    MCU_SCL=0;
    }

  return bytedata;

  }


/*==============================================================================

==============================================================================*/
void Send_Acknowledge(bit ack) {

  MCU_SDA=ack;
  MCU_SCL=1;
  MCU_SCL=0;

  }


/*==============================================================================

==============================================================================*/
unsigned char EE_MCU_Byte_Read(unsigned int address) {

  unsigned char device, bytedata;

  device=EE_MCU|(address/256)*2;
  bytedata=0;

  Again:
    IIC_Start();
    if(IIC_Data_In(device))
      goto Again;
    if(IIC_Data_In(address%256))
      goto Again;
    IIC_Start();
    if(IIC_Data_In(device|1))
      goto Again;
    bytedata=IIC_Data_Out();
    Send_Acknowledge(1);
    IIC_Stop();

  return bytedata;

  }


/*==============================================================================

==============================================================================*/
void EE_MCU_Byte_Write(unsigned int address, unsigned char bytedata) {

  unsigned char device;

  device=EE_MCU|(address/256)*2;

  Again:
    IIC_Start();
    if(IIC_Data_In(device))
      goto Again;
    if(IIC_Data_In(address%256))
      goto Again;
    if(IIC_Data_In(bytedata))
      goto Again;
    IIC_Stop();

  }