***************************************************************************/
#ifndef _REAL_TIMER_DS1302_2003_7_21_
#define _REAL_TIMER_DS1302_2003_7_21_

sbit  DS1302_CLK = P1^6;              //實時時鐘時鐘線引腳
sbit  DS1302_IO  = P1^7;              //實時時鐘數據線引腳
sbit  DS1302_RST = P1^5;              //實時時鐘復位線引腳
sbit  ACC0 = ACC^0;
sbit  ACC7 = ACC^7;

typedef struct __SYSTEMTIME__
{
 unsigned char Second;
 unsigned char Minute;
 unsigned char Hour;
 unsigned char Week;
 unsigned char Day;
 unsigned char Month;
 unsigned char  Year;
 unsigned char DateString[9];
 unsigned char TimeString[9];
}SYSTEMTIME; //定義的時間類型

#define AM(X) X
#define PM(X) (X+12)               // 轉成24小時制
#define DS1302_SECOND 0x80
#define DS1302_MINUTE 0x82
#define DS1302_HOUR  0x84
#define DS1302_WEEK  0x8A
#define DS1302_DAY  0x86
#define DS1302_MONTH 0x88
#define DS1302_YEAR  0x8C
#define DS1302_RAM(X) (0xC0+(X)*2)    //用于計算 DS1302_RAM 地址的宏

void DS1302InputByte(unsigned char d)  //實時時鐘寫入一字節(內部函數)
{
    unsigned char i;
    ACC = d;
    for(i=8; i>0; i--)
    {
        DS1302_IO = ACC0;            //相當于匯編中的 RRC
        DS1302_CLK = 1;
        DS1302_CLK = 0;
        ACC = ACC >> 1;
    }
}

unsigned char DS1302OutputByte(void)  //實時時鐘讀取一字節(內部函數)
{
    unsigned char i;
    for(i=8; i>0; i--)
    {
        ACC = ACC >>1;            //相當于匯編中的 RRC
        ACC7 = DS1302_IO;
        DS1302_CLK = 1;
        DS1302_CLK = 0;
    }
    return(ACC);
}

void Write1302(unsigned char ucAddr, unsigned char ucDa) //ucAddr: DS1302地址, ucData: 要寫的數據
{
    DS1302_RST = 0;
    DS1302_CLK = 0;
    DS1302_RST = 1;
    DS1302InputByte(ucAddr);        // 地址，命令
    DS1302InputByte(ucDa);        // 寫1Byte數據
    DS1302_CLK = 1;
    DS1302_RST = 0;
}

unsigned char Read1302(unsigned char ucAddr) //讀取DS1302某地址的數據
{
    unsigned char ucData;
    DS1302_RST = 0;
    DS1302_CLK = 0;
    DS1302_RST = 1;
    DS1302InputByte(ucAddr|0x01);        // 地址，命令
    ucData = DS1302OutputByte();         // 讀1Byte數據
    DS1302_CLK = 1;
    DS1302_RST = 0;
    return(ucData);
}

void DS1302_SetProtect(bit flag)        //是否寫保護
{
 if(flag)
  Write1302(0x8E,0x10);
 else
  Write1302(0x8E,0x00);
}

void DS1302_SetTime(unsigned char Address, unsigned char Value)        // 設置時間函數
{
 DS1302_SetProtect(0);
 Write1302(Address, ((Value/10)<<4 | (Value%10)));
}

void DS1302_GetTime(SYSTEMTIME *Time)
{
 unsigned char ReadValue;
 ReadValue = Read1302(DS1302_SECOND);
 Time->Second = ((ReadValue&0x70)>>4)*10 + (ReadValue&0x0F);
 ReadValue = Read1302(DS1302_MINUTE);
 Time->Minute = ((ReadValue&0x70)>>4)*10 + (ReadValue&0x0F);
 ReadValue = Read1302(DS1302_HOUR);
 Time->Hour = ((ReadValue&0x70)>>4)*10 + (ReadValue&0x0F);
 ReadValue = Read1302(DS1302_DAY);
 Time->Day = ((ReadValue&0x70)>>4)*10 + (ReadValue&0x0F); 
 ReadValue = Read1302(DS1302_WEEK);
 Time->Week = ((ReadValue&0x70)>>4)*10 + (ReadValue&0x0F);
 ReadValue = Read1302(DS1302_MONTH);
 Time->Month = ((ReadValue&0x70)>>4)*10 + (ReadValue&0x0F);
 ReadValue = Read1302(DS1302_YEAR);
 Time->Year = ((ReadValue&0x70)>>4)*10 + (ReadValue&0x0F); 
}

void DateToStr(SYSTEMTIME *Time)
{
 Time->DateString[0] = Time->Year/10 + '0';
 Time->DateString[1] = Time->Year%10 + '0';
 Time->DateString[2] = '-';
 Time->DateString[3] = Time->Month/10 + '0';
 Time->DateString[4] = Time->Month%10 + '0';
 Time->DateString[5] = '-';
 Time->DateString[6] = Time->Day/10 + '0';
 Time->DateString[7] = Time->Day%10 + '0';
 Time->DateString[8] = '\0';
}

void TimeToStr(SYSTEMTIME *Time)
{
 Time->TimeString[0] = Time->Hour/10 + '0';
 Time->TimeString[1] = Time->Hour%10 + '0';
 Time->TimeString[2] = ':';
 Time->TimeString[3] = Time->Minute/10 + '0';
 Time->TimeString[4] = Time->Minute%10 + '0';
 Time->TimeString[5] = ':';
 Time->TimeString[6] = Time->Second/10 + '0';
 Time->TimeString[7] = Time->Second%10 + '0';
 Time->DateString[8] = '\0';
}

void Initial_DS1302(void)
{
 unsigned char Second=Read1302(DS1302_SECOND);
 if(Second&0x80)   
  DS1302_SetTime(DS1302_SECOND,0);
}

在protues中，如果程序沒有對DS1302進行寫操作，那么Protues會默認把電腦時間寫入DS1302
所以，如果你的驅動程序沒有正確的對DS1302寫入時間，Protues里就會顯示電腦當前的時間