分享一个基于DS12C887和LCD1602显示的数字时钟，下面是仿真原理图：

单片机源程序如下：

#include <AT89X52.h>
#define DSbus P0
#define LCDbus P1

//定义DS12C887和LCD的控制线
sbit DS_CS = P2^7; //引脚13,片选信号输入,低电平有效。
sbit DS_AS = P2^4; //引脚14,地址选通输入。
sbit DS_RW = P2^5; //引脚15,读/写输入。
sbit DS_DS = P2^6; //引脚17,数据选通或读输入。
sbit LCD_RS=P2^0;
sbit LCD_EN=P2^2;
//时间变量定义
unsigned char Counter;
unsigned char Hour,Min,Sec,Year,Month,Date,Week;

/*DS12CR887驱动程序---------------------------------------------------------------------------*/
//往DS12CR887写数据函数
void DS12887write(unsigned char add,unsigned char Date)
{
DS_CS=0;
DS_DS=1;
DS_RW=1;
DS_AS=1;
DSbus=add;
DS_AS=0;
DS_RW=0;
DSbus=Date;
DS_RW=1;
DS_AS=1;
DS_CS=1;
}
//读取DS12CR887数据函数
unsigned char DS12887read(unsigned char add)
{
unsigned char z;
DS_CS=0;
DS_RW=1;
DS_DS=1;
DS_AS=1;
DSbus=add;
DS_AS=0;
DS_DS=0;
DSbus=0xff;
z=DSbus;
DS_DS=1;
DS_AS=1;
DS_CS=1;
return z;
}
//DS12CR887初始化函数
void DS12887LCDinit()
{
DS_AS=0; DS_DS=0; DS_RW=0;
DS12887write(0x0a,0x20);//DS12CR887寄存器A功能设置，开启时钟振荡器
DS12887write(0x0b,0x06);//寄存器B功能设置，不开启闹钟中断使能，数据模式为二进制，24小时模式。
//DS12887write(4,0x8);DS12887write(2,0x00);DS12887write(0,0x00); //给DS12CR887的时分秒赋值，开机后显示8:00:00
}
void Delay(unsigned int z)
{
unsigned int x,y;
for(x=z;x>0;x--)
for(y=110;y>0;y--);
}
void LCDwritecom(unsigned char com)
{
LCD_RS=0;
LCDbus=com;
Delay(5);
LCD_EN=1;
Delay(5);
LCD_EN=0;
}
void LCDwritecomdata(unsigned char dat)
{
LCD_RS=1;
LCDbus=dat;
Delay(5);
LCD_EN=1;
Delay(5);
LCD_EN=0;
}
void LCDinit()
{
LCD_EN=0;
LCDwritecom(0x38);
LCDwritecom(0x0c);
LCDwritecom(0x06);
LCDwritecom(0x01);
LCDwritecom(0x80);
}
void Timedisplay(void)
{
//LCDwritecom(1);
LCDwritecom(0x80);
//往液晶屏填写"小时"数据-----------------------------------------------
Hour=DS12887read(4); //读取DS12CR887的小时数据
if((Hour/10)==0)LCDwritecomdata(0);
else LCDwritecomdata(Hour/10+0x30);//小时十位
LCDwritecomdata(Hour%10+0x30); //小时个位
LCDwritecomdata(':'); //时钟分隔符":"
//往液晶屏填写"分钟"数据-----------------------------------------------
Min=DS12887read(2); //读取DS12CR887的分数据
LCDwritecomdata(Min/10+0x30);
LCDwritecomdata(Min%10+0x30);
LCDwritecomdata(':'); //时钟分隔符":"
//往液晶屏填写"秒"数据-------------------------------------------------
Sec=DS12887read(0); //读取DS12CR887的秒数据
LCDwritecomdata(Sec/10+0x30);
LCDwritecomdata(Sec%10+0x30);
Delay(100);
}
void Datedisplay(void)
{
//LCDwritecom(1);
LCDwritecom(0xc0);
//往液晶屏填写"年"数据-----------------------------------------------
LCDwritecomdata('2');
LCDwritecomdata('0');
Year=DS12887read(9); //读取DS12CR887的年数据

LCDwritecomdata(Year/10+0x30);//年十位
LCDwritecomdata(Year%10+0x30); //年个位
LCDwritecomdata('/'); //时钟分隔符":"
//往液晶屏填写"月"数据-----------------------------------------------
Month=DS12887read(8); //读取DS12CR887的月数据
LCDwritecomdata(Month/10+0x30);
LCDwritecomdata(Month%10+0x30);
LCDwritecomdata('/'); //时钟分隔符":"
//往液晶屏填写"日"数据-------------------------------------------------
Date=DS12887read(7); //读取DS12CR887的日数据
LCDwritecomdata(Date/10+0x30);
LCDwritecomdata(Date%10+0x30);
//往液晶屏填写"星期"数据-------------------------------------------------
Week=DS12887read(6); //读取DS12CR887的日数据
LCDwritecomdata(0);
LCDwritecomdata(Week-1+0x30);
Delay(100);
}
void main()
{
// unsigned char i;
LCDinit();
DS12887LCDinit();
DS12887write(0x0a,0x00); //开始调时，DS12CR887关闭时钟振荡器
DS12887write(0,55); //秒
DS12887write(2,59);
DS12887write(4,23);
DS12887write(6,5); //星期
DS12887write(7,22); //日
DS12887write(8,9); //
DS12887write(9,12); //
//display_Date();
while(1)
{
Timedisplay();
Datedisplay();
Delay(100);
}
}