高精度实时时钟－SD2001驱动程序

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

//用户调用函数

//void initSD2001Time(unsigned char year,unsigned char month,unsigned char day,unsigned char date,unsigned char hour,unsigned char minute,unsigned char second)

//时钟初始化函数 年，月，日，星期，小时，分钟，秒

//ReadSD2001_Time()

//读时间函数 结果分别存放在全局变量 SD2001_year SD2001_month ;SD2001_day ;SD2001_date ;SD2001_hour ;SD2001_minute;SD2001_second;中</P><P>

#include "reg51.h"

#include "intrins.h"

sbit SD2001_SDA= P2^1;

sbit SD2001_SCL= P2^3;

sbit SCLE = P1^5;

sbit SDAE = P1^4;#define SomeNOP(); { _nop_(); _nop_(); _nop_();_nop_(); }

unsigned char SD2001_year ;

unsigned char SD2001_month ;

unsigned char SD2001_day ;

unsigned char SD2001_date ;

unsigned char SD2001_hour ;

unsigned char SD2001_minute;

unsigned char SD2001_second;

unsigned char LishiSRAM[7];

/*--------------------------------------------------------------------------------

调用方式：void SD2001_I2CStart(void) ﹫2001/07/0 4

函数说明：私有函数，I2C专用

---------------------------------------------------------------------------------*/

void SD2001_I2CStart(void)

{

EA=0;

SD2001_SCL=0;

SD2001_SDA=1; SomeNOP();

SD2001_SCL=1; SomeNOP();//INI

SD2001_SDA=0; SomeNOP(); //START

SD2001_SCL=0;

}</P><P>void I2CStartRAM(void)

{

EA=0;

SCLE=0;

SDAE=1; SomeNOP();

SCLE=1; SomeNOP();//INI

SDAE=0; SomeNOP(); //START

SCLE=0;

}

/*--------------------------------------------------------------------------------

调用方式：void SD2001_I2CStop(void) ﹫2001/07/0 4

函数说明：私有函数，I2C专用

---------------------------------------------------------------------------------*/

void SD2001_I2CStop(void)

{

SD2001_SDA=0;

SD2001_SCL=0; SomeNOP(); //INI

SD2001_SCL=1; SomeNOP();

SD2001_SDA=1; SomeNOP();//STOP

SD2001_SCL=0;

EA=1;

}</P><P>void I2CStopRAM(void)

{

SDAE=0;

SCLE=0; SomeNOP(); //INI

SCLE=1; SomeNOP();

SDAE=1; SomeNOP();//STOP

SCLE=0;

EA=1;

}

/*--------------------------------------------------------------------------------

调用方式：void I2CSend(unsigned char ch) ﹫2001/07/0 5

函数说明：私有函数，I2C专用

MSB

---------------------------------------------------------------------------------*/

void SD2001_I2CSendByte(unsigned char ch)

{

unsigned char i=8;

while(i--)

{

SD2001_SCL=0;_nop_();

SD2001_SDA=(bit)(ch&0x80); ch<<=1; SomeNOP();

SD2001_SCL=1; SomeNOP();

}

SD2001_SCL=0;

// WaitAck();

}

/*--------------------------------------------------------------------------------

调用方式：void I2CSend(unsigned char ch) ﹫2001/07/0 5

函数说明：私有函数，I2C专用

LSB

---------------------------------------------------------------------------------*/

void SD2001_I2CSendByte1(unsigned char ch)

{

unsigned char i=8;

while(i--)

{

SD2001_SCL=0;_nop_();

SD2001_SDA=(bit)(ch & 0x01); ch>>=1; SomeNOP();

SD2001_SCL=1; SomeNOP();

}

SD2001_SCL=0;

//WaitAck();

}

//ACK

bitout()

{

SD2001_SDA=0;

SD2001_SCL=0;

SD2001_SDA=0;

SomeNOP();

SD2001_SCL=1; SomeNOP();

SD2001_SCL=0;

}

//接受时钟的1位

bit bitin()

{

bit temp;

SD2001_SDA=1;

SD2001_SCL=0;

SomeNOP();

temp=SD2001_SDA;

SomeNOP();

SD2001_SCL=1;

SomeNOP();

SD2001_SCL=0;

return(temp);

}

//接受时钟的1个字节

unsigned char rx()

{

unsigned char i=8;

unsigned char dat=0;

while(i--)

{

dat>>=1;

if(bitin())

dat=dat|0x80;

}

return(dat);

}

/*-------------SRAM-------------*/

SRAMACK()

{

SCLE=0; SomeNOP(); //ACK

SDAE=0; SomeNOP();

SCLE=1; SomeNOP();

SCLE=0; SomeNOP();

}

void SRAMSent(unsigned char ch) //发送一个字节给RAM

{

unsigned char i=8;

while(i--)

{

SCLE=0;_nop_();

SDAE=(bit)(ch&0x80); ch<<=1; SomeNOP();

SCLE=1; SomeNOP();

SCLE=0;

}

SDAE=1;

SCLE=0; SomeNOP(); //ACK

SCLE=1; SomeNOP(); //ACK

while(SDAE==1){} //ACK

SCLE=0;

}

SRAMRX() //接收一个字节从RAM

{

unsigned char i=8,dat=0;

SCLE=0;SomeNOP();

SDAE=1;SomeNOP();

while(i--)

{

SCLE=1;SomeNOP();

dat<<=1;

dat|=SDAE;

SCLE=0;

}

return(dat);

}

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

//改时钟

void initSD2001Time(unsigned char year,unsigned char month,unsigned char day,unsigned char date,unsigned char hour,unsigned char minute,unsigned char second)

{

SD2001_I2CStart();

SD2001_I2CSendByte(0x64); //从年开始写

bitout();</P><P> SD2001_I2CSendByte1(year); //写入年

bitout();

SD2001_I2CSendByte1(month);

bitout();

SD2001_I2CSendByte1(day);

bitout();

SD2001_I2CSendByte1(date);

bitout();

SD2001_I2CSendByte1(hour);

bitout();

SD2001_I2CSendByte1(minute);

bitout();

SD2001_I2CSendByte1(second);

bitout();

SD2001_I2CStop();

}</P><P>//读时间

ReadSD2001_Time()

{

unsigned char time[8]=0,i;

SD2001_I2CStart();

SD2001_I2CSendByte(0x65); //从年开始读

bitout();

i=8;

while(i--)

{

time[i]=rx();

bitout();

}

SD2001_I2CStop();

SD2001_year =time[7];

SD2001_month =time[6];

SD2001_day =time[5];

SD2001_date =time[4];

SD2001_hour =time[3]&0x7F;

SD2001_minute=time[2];

SD2001_second=time[1];

}

//时钟初始化

InitSD2001()

{

SD2001_I2CStart();

SD2001_I2CSendByte(0x62);//写状态寄存器

bitout();

SD2001_I2CSendByte1(0xC2);//Power 12/24 INT1AE INT2AE INT1ME INT2ME INT1FE INT2FE

// 1 1 0 0 0 0 1 0

SD2001_I2CStop();

}</P><P>//向ram写入数据

SaveToSRAM(unsigned int Address,unsigned char SRAM_Dat)

{

unsigned char AddrH,AddrL;

AddrL=Address;

AddrH=Address>>8;

I2CStartRAM();

SRAMSent(0xA0); //送关键字

SRAMSent(AddrH); //送高地址 已经含ACK

SRAMSent(AddrL); //送低地址

SRAMSent(SRAM_Dat);

I2CStopRAM();

}//从ram中读取数据

LoadFromSRAM(unsigned int Address)

{

unsigned char AddrH,AddrL,Dat;

AddrL=Address;

AddrH=Address>>8;

I2CStartRAM();

SRAMSent(0xA0); //送关键字

SRAMSent(AddrH); //送高地址 已经含ACK

SRAMSent(AddrL); //送低地址

I2CStartRAM();

SRAMSent(0xA1);

Dat=SRAMRX();

I2CStopRAM();

return(Dat);

}

////////////////////////////////////////

main()

{

unsigned char a;

InitSD2001();

//initSD2001Time(0x03,0x01,0x20,0x01,0x15,0x50,0x00);//对表

ReadSD2001_Time();

SaveToSRAM(5,20);

a=LoadFromSRAM(5);</P><P>

while(1)

{

ReadSD2001_Time();

_nop_();

}

}