用定時器中斷設計時鐘，用1602液晶顯示；

參考原始碼如下：

#include

#define uchar unsigned char

sbit rd=P2^6;

sbit wr=P2^5;

sbit lcde=P2^7;

sbit k1=P1^0;

sbit k2=P1^1;

sbit k4=P1^3;

sbit k8=P1^7;

uchar code table1[]=" 2011-10-01 SAT";

uchar code table2[]="00:00:00";

uchar t,s1num;

char shi,fen,miao;

void delay(uchar z) //延遲zms函式

{

uchar x,y;

for(x=z;x>0;x--)

for(y=110;y>0;y--);

}

void write_com(uchar com) //液晶寫指令操作

{

rd=0;

wr=0;

delay(5);

lcde=1;

P0=com;

lcde=0;

}

void write_date(uchar date) //液晶寫資料操作

{

rd=1;

wr=0;

delay(5);

lcde=1;

P0=date;

lcde=0;

}

void write_sfm(uchar add,uchar date) //更新時分秒

{

uchar shi,ge;

shi=date/10;

ge=date;

write_com(0x80+0x40+add);

write_date(0x30+shi);

write_date(0x30+ge);

}

void init() //初始化函式

{

uchar i;

write_com(0x38);

write_com(0x0c);

write_com(0x06);

write_com(0x01);

write_com(0x80+0x00);

for(i=0;i

write_date(table1[i]);

write_com(0x80+0x46);

for(i=0;i

write_date(table2[i]);

TMOD=0x01; //定時器工作方式

TH0=(65536-50000)/256; //設定定時器初值

TL0=(65536-50000)%6; //12M晶振時ms數為

EA=1;

ET0=1;

TR0=1;

}

void keyscan() //鍵盤掃描函式

{

if(k1==0) //按下k1鍵確定調時分秒

{

delay(5);

if(k1==0)

{

s1num++;

while(!k1)

;

delay(5);

while(!k1);

if(s1num==1)

{

TR0=0; //暫停計時器

write_com(0x80+0x4d); //游標在秒的位置閃爍

write_com(0x0f);

}

if(s1num==2) //游標在分的位置

{

TR0=0;

write_com(0x80+0x4a);

write_com(0x0f);

}

if(s1num==3)

{

TR0=0;

write_com(0x80+0x47);

write_com(0x0f);

}

if(s1num==4) //按下第四下時接著走時

{

s1num=0;

write_com(0x0c);

TR0=1;

}

}

}

if(s1num!=0)

{

if(s1num==1)

{

if(k2==0) //按k2鍵秒加

{

delay(5);

if(k2==0)

{

while(!k2);

delay(5);

while(!k2);

miao++;

if(miao==60)

miao=0;

write_sfm(0x0c,miao);

write_com(0x80+0x4d);

}

}

}

if(s1num==2)

{

if(k2==0) //分加

{

delay(5);

if(k2==0)

{

while(!k2);

delay(5);

while(!k2);

fen++;

if(fen==60)

fen=0;

write_sfm(0x09,fen);

write_com(0x80+0x4a);

}

}

}

if(s1num==3)

{

if(k2==0) //時加

{

delay(5);

if(k2==0)

{

while(!k2);

delay(5);

while(!k2);

shi++;

if(shi==24)

shi=0;

write_sfm(0x06,shi);

write_com(0x80+0x47);

}

}

}

if(k4==0) //判斷k3是否被按下

{

delay(5);

if(k4==0)

{

while(!k4);

delay(5);

while(!k4);

if(s1num==1)

{

miao--; //秒減

if(miao==-1)

miao=59;

write_sfm(0x0c,miao);

write_com(0x80+0x4d);

}

if(s1num==2)

{

fen--; //分減

if(fen==-1)

fen=59;

write_sfm(0x09,fen);

write_com(0x80+0x4a);

}

if(s1num==3)

{

shi--; //時減

if(shi==-1)

shi=23;

write_sfm(0x06,shi);

write_com(0x80+0x47);

}

}

}

}

if(k8==0) // 按下k8退出調時

{

delay(5);

if(k8==0)

{

while(!k8);

delay(5);

while(!k8);

s1num=0;

write_com(0x0c);

TR0=1;

}

}

}

void main()

{

init();

while(1)

{

keyscan();

}

}

void timer0() interrupt 1 //中斷服務程式

{

TH0=(65536-50000)/256;

TL0=(65536-50000)%6; //重新設定定時器初值

t++;

if(t==20) //定時器中斷次為秒

{

t=0;

miao++;

if(miao==60)

{

miao=0;

fen++;

if(fen==60)

{

fen=0;

shi++;

if(shi==24)

{

shi=0;

}

write_sfm(0x06,shi); //顯示時

}

write_sfm(0x09,fen); //顯示分

}

write_sfm(0x0c,miao); //顯示秒

}

}