常用程序模块备份（一）：STC12C5A60S2自带EEPROM

其实早就应该养成一个良好的程序备份习惯，现在放在这里即方便自己随时在其他地方调用、备份，也可以帮到需要的人。
对于stc自带EEPROM来说，用起来唯一不太方便的地方就是每次修改任何一个字节需要将整个扇区都擦除才能修改，所以每次修改都要讲整个扇区内容用数组全部读出缓存起来，进行擦除操作，讲需要修改的内容在相应的数组位置修改好，再讲整个数组内容重新写入到EEPROM里，头文件中我已经将接口函数都写好啦。直接调用就行，不用考虑任何问题，而且地址也直接从0开始到 USING_CHAR_NUM-1（USING_CHAR_NUM最大可到512）

EEPROM.h-----------------------------------------------------------------------------------------------------
#ifndef __EEPROM_H__
#define __EEPROM_H__

unsigned char EepromReadByte(unsigned char addr);

void EepromWriteByte(unsigned char addr, unsigned char dat);
#endif

EEPROM.c-----------------------------------------------------------------------------------------------------
#include "intrins.h"
typedef unsigned char BYTE;
typedef unsigned int WORD;

sfr  IAP_DATA      =   0xC2;               //Flash data register
sfr  IAP_ADDRH     =   0xC3;              //Flash address HIGH
sfr  IAP_ADDRL     =   0xC4;              //Flash address LOW
sfr  IAP_CMD       =   0xC5;              //Flash command register
sfr  IAP_TRIG      =   0xC6;              //Flash command trigger
sfr  IAP_CONTR     =   0xC7;              //Flash control register

#define   CMD_IDLE      0                 //Stand-By
#define   CMD_READ      1                 //Byte-Read
#define   CMD_PROGRAM   2                 //Byte-Program
#define   CMD_ERASE     3                 //Sector-Erase

#define   ENABLE_IAP    0x82              //if SYSCLK<20MHz
//Start address for STC12C5A60S2 series EEPROM
#define   IAP_ADDRESS   0x0000
#define      USING_CHAR_NUM   11

void IapIdle();
BYTE IapReadByte(WORD addr);
void IapProgramByte(WORD addr, BYTE dat);
void IapEraseSector(WORD addr);

unsigned char EepromReadByte(unsigned char addr)
{
    return(IapReadByte(addr));
}

void EepromWriteByte(unsigned char addr, unsigned char dat)
{
    unsigned char eepromBUF[USING_CHAR_NUM];
    unsigned char i;
    for(i=0; i< USING_CHAR_NUM; i++)
    {
        eepromBUF[IAP_ADDRESS+i] = IapReadByte(IAP_ADDRESS+i);  
    }
    if(addr < USING_CHAR_NUM)
    {
        eepromBUF[IAP_ADDRESS+addr] = dat;
        IapEraseSector(IAP_ADDRESS);

        for(i=0; i< USING_CHAR_NUM; i++)
        {
            IapProgramByte(IAP_ADDRESS+i, eepromBUF[IAP_ADDRESS+i]);  
        }
    }
}
//void EepromInit(void)
//{
//    unsigned int tmp = 0;
//    _nop_();
//    _nop_();
//    _nop_();
//    tmp = IapReadByte(IAP_ADDRESS+1);
//    tmp = (tmp << 8) + IapReadByte(IAP_ADDRESS);
//    if(0xffff == tmp)
//    {
//        IapProgramByte(IAP_ADDRESS,(BYTE)0);
//        IapProgramByte(IAP_ADDRESS+1,(BYTE)0);
//        tmp = 0;  
//    }
//    tmp++;
//    IapEraseSector(IAP_ADDRESS);
//    IapProgramByte(IAP_ADDRESS,(BYTE)tmp );
//    IapProgramByte(IAP_ADDRESS+1,(BYTE)(tmp>>8) );
//      
//}

void IapIdle()
{
      IAP_CONTR = 0;      //Close IAP function
      IAP_CMD = 0;            //Clear command to standby
      IAP_TRIG = 0;                      //Clear trigger register
      IAP_ADDRH = 0x80;                 //Data ptr point to non-EEPROM area
      IAP_ADDRL = 0;                     //Clear IAP address to prevent misuse
}

BYTE IapReadByte(WORD addr)
{
      BYTE dat;                          //Data buffer
      IAP_CONTR = ENABLE_IAP;   //Open IAP function, and set wait time
      IAP_CMD = CMD_READ;        //Set ISP/IAP/EEPROM READ command
      IAP_ADDRL = addr;                 //Set ISP/IAP/EEPROM address low
      IAP_ADDRH = addr >> 8;      //Set ISP/IAP/EEPROM address high
      IAP_TRIG = 0x5a;                //Send trigger command1 (0x5a)
      IAP_TRIG = 0xa5;                  //Send trigger command2 (0xa5)
      _nop_();  _nop_();                          //MCU will hold here until ISP/IAP/EEPROM
      //operation complete
      dat = IAP_DATA;            //Read ISP/IAP/EEPROM data
      IapIdle();                         //Close ISP/IAP/EEPROM function
      return dat;                        //Return Flash data
}

void IapProgramByte(WORD addr, BYTE dat)
{
  IAP_CONTR = ENABLE_IAP;         //Open IAP function, and set wait time
      IAP_CMD = CMD_PROGRAM;     //Set ISP/IAP/EEPROM PROGRAM command
      IAP_ADDRL = addr;                 //Set ISP/IAP/EEPROM address low
      IAP_ADDRH = addr >> 8;            //Set ISP/IAP/EEPROM address high
      IAP_DATA = dat;                  //Write ISP/IAP/EEPROM data
      IAP_TRIG = 0x5a;                   //Send trigger command1 (0x5a)
      IAP_TRIG = 0xa5;                   //Send trigger command2 (0xa5)
      _nop_();   _nop_();                        //MCU will hold here until ISP/IAP/EEPROM
      //operation complete
      IapIdle();
}

void IapEraseSector(WORD addr)
{
      IAP_CONTR = ENABLE_IAP;  //Open IAP function, and set wait time
      IAP_CMD = CMD_ERASE;      //Set ISP/IAP/EEPROM ERASE command
      IAP_ADDRL = addr;                //Set ISP/IAP/EEPROM address low
      IAP_ADDRH = addr >> 8;         //Set ISP/IAP/EEPROM address high
      IAP_TRIG = 0x5a;                   //Send trigger command1 (0x5a)
      IAP_TRIG = 0xa5;                   //Send trigger command2 (0xa5)
      _nop_();  _nop_();                         //MCU will hold here until ISP/IAP/EEPROM
      //operation complete
      IapIdle();
}