51单片机实现万年历利用AT89S52单片机的P0口来和另外几个口来控制1602液晶的显示和P1口还有其它口来控制ds12887时钟芯片。

设置四个按键，1个定义为时间设置功能键，一个定义为闹钟设置功能键，另外两个用来调节时间的增减。

原理图：pcb图：源程序：#include<reg52.h>#define uint unsigned int#define uchar unsigned charsbit beep=P2^0;//蜂鸣器控制口sbit timeadd=P2^1;//调节时间加sbit timesub=P2^2;//调节时间减sbit timeclk=P2^3;//闹钟设定键sbit timefun=P2^4;//时间设定键sbit lcdrs=P2^5;//液晶的命令和数据控制口sbit ledrw=P2^6;//液晶的写数据口sbit lcden=P2^7;//液晶显示模块的使能端sbit timeds=P3^3;//时钟芯片地址闸sbit timerw=P3^4;//时钟芯片读写sbit timeas=P3^5;//时钟芯片地址闸sbit timeen=P3^6;//时钟芯片片选uchar code table[]="20 - - week ";uchar code table1[]=" : : ";//要显示的字符串char num,shi,fen,miao,nian=2000,yue,ri,week,numfun,anumfun,flag,flag1; uchar leap;void delay(uint x){uchar i,j;for(i=x;i>0;i--)for(j=110;j>0;j--);}void didi(){beep=0;delay(1000);beep=1;delay(1000);}void write_(uchar ){lcdrs=0;P0=;delay(5);lcden=1;delay(20);lcden=0;}void write_date(uchar date){lcdrs=1;P0=date;delay(5);lcden=1;delay(20);lcden=0;}void write_sfm(uchar add,uchar date){ uchar shi,ge;shi=date/10;ge=date%10;write_(0x80+0x40+add);write_date(0x30+shi);write_date(0x30+ge);}void write_nyr(uchar add,uchar date){ uchar shi,ge;shi=date/10;ge=date%10;write_(0x80+add);write_date(0x30+shi);write_date(0x30+ge);}void write_zhou(uchar add,uchar date) {write_(0x80+add);write_date(0x30+date);}void write_ds(uchar add,uchar date){ timeen=0;timeas=1;timeds=1;timerw=1;P1=add;timeas=0;timerw=0;P1=date;timerw=1;timeas=1;timeen=1;}uchar read_ds(uchar add){uchar ds_date;timeas=1;timeds=1;timerw=1;timeen=0;P1=add;timeas=0;timeds=0;P1=0xff;ds_date=P1;timeds=1;timeas=1;timeen=1;return ds_date;}void keyscan(){if(flag1==1)//用来关闭闹钟铃声{if(timeadd==0){delay(5);if(timeadd==0){while(!timeadd==0);flag1=0;}}if(timesub==0){delay(5);if(timesub==0){while(!timesub==0);flag1=0;}}}if(timefun==0){delay(5);if(timefun==0){while(!timefun);flag=1;numfun++;if(numfun==1){write_(0x80+0x40+0x0a);write_(0x0f);}if(numfun==2){write_(0x80+0x40+0x07);write_(0x0f);}if(numfun==3){write_(0x80+0x40+0x04);write_(0x0f);}if(numfun==4){write_(0x80+0x0f);write_(0x0f);}if(numfun==5){write_(0x80+0x09);write_(0x0f);}if(numfun==6){write_(0x80+0x06);write_(0x0f);}if(numfun==7){write_(0x80+0x03);write_(0x0f);}if(numfun==8){numfun=0;flag=0;}}}if(numfun!=0){if(timeadd==0){delay(5);while(!timeadd);if(numfun==1){miao++;if(miao==60)miao=0;write_sfm(9,miao);write_(0x80+0x40+9);write_ds(0,miao);}if(numfun==2){fen++;if(fen==60)fen=0;write_sfm(6,fen);write_(0x80+0x40+6);write_ds(2,fen);}if(numfun==3){shi++;if(shi==24)shi=0;write_sfm(3,shi);write_(0x80+0x40+3);write_ds(4,shi);}if(numfun==4){week++;if(week==8)week=1;write_zhou(0x0f,week);write_(0x80+0x0f);write_ds(6,week);}if(numfun==5){if(nian==0){switch(yue){case 1:ri++;if(ri==32) ri=1;break;case 2:ri++;if(ri==30) ri=1;break;case 3:ri++;if(ri==32) ri=1;break;case 4:ri++;if(ri==31) ri=1;break;case 5:ri++;if(ri==32) ri=1;break;case 6:ri++;if(ri==31) ri=1;break;case 7:ri++;if(ri==32) ri=1;break;case 8:ri++;if(ri==32) ri=1;break;case 9:ri++;if(ri==31)ri=1;break;case 10:ri++;if(ri==32)ri=1;break;case 11:ri++;if(ri==31)ri=1;break;case 12:ri++;if(ri==32)ri=1;break;}}else if(leap&&yue==2){ri++;if(ri==30)ri=1;}else if(yue==2&&leap==0){ri++;if(ri==29)ri=1;}elseswitch(yue){case 1:ri++;if(ri==32) ri=1;break;case 3:ri++;if(ri==32) ri=1;break;case 4:ri++;if(ri==31) ri=1;break;case 5:ri++;if(ri==32) ri=1;break;case 6:ri++;if(ri==31) ri=1;break;case 7:ri++;if(ri==32) ri=1;break;case 8:ri++;if(ri==32) ri=1;break;case 9:ri++;if(ri==31) ri=1;break;case 10:ri++;if(ri==32) ri=1;break;case 11:ri++;if(ri==31) ri=1;break;case 12:ri++;if(ri==32) ri=1;break;}write_nyr(8,ri);write_(0x80+0x08);write_ds(7,ri);}if(numfun==6){yue++;if(yue==13)yue=0;write_nyr(5,yue);write_(0x80+0x05);write_ds(8,yue);}if(numfun==7){nian++;if(nian==100)nian=0;leap=nian%4==0&&nian%100!=0;write_nyr(2,nian);write_(0x80+2);write_ds(9,nian);}}if(timesub==0){delay(5);while(!timesub);if(numfun==1){miao--;if(miao==-1)miao=59;write_sfm(9,miao);write_(0x80+0x40+9);write_ds(0,miao);}if(numfun==2){fen--;if(fen==-1)fen=59;write_sfm(6,fen);write_(0x80+0x40+6);write_ds(2,fen);}if(numfun==3){shi--;if(shi==-1)shi=23;write_sfm(3,shi);write_(0x80+0x40+3);write_ds(4,shi);}if(numfun==4){week--;if(week==0)week=7;write_zhou(0x0f,week);write_(0x80+0x0f);write_ds(6,week);}if(numfun==5){if(nian==0){switch(yue){case 1:ri--;if(ri==0) ri=31;break;case 2:ri--;if(ri==0) ri=29;break;case 3:ri--;if(ri==0) ri=31;break;case 4:ri--;if(ri==0) ri=30;break;case 5:ri--;if(ri==0) ri=31;break;case 6:ri--;if(ri==0) ri=30;break;case 7:ri--;if(ri==0) ri=31;break;case 8:ri--;if(ri==0) ri=31;break;case 9:ri--;if(ri==0) ri=30;break;case 10:ri--;if(ri==0) ri=31;break;case 11:ri--;if(ri==0) ri=30;break;case 12:ri--;if(ri==0) ri=31;break;}}else if(leap&&yue==2){ri--;if(ri==0)ri=29;}else if(yue==2&&leap==0){ri--;if(ri==0)ri=28;}elseswitch(yue){case 1:ri--;if(ri==0) ri=31;break;case 3:ri--;if(ri==0) ri=31;break;case 4:ri--;if(ri==0) ri=30;break;case 5:ri--;if(ri==0) ri=31;break;case 6:ri--;if(ri==0) ri=30;break;case 7:ri--;if(ri==0) ri=31;break;case 8:ri--;if(ri==0) ri=31;break;case 9:ri--;if(ri==0) ri=30;break;case 10:ri--;if(ri==0) ri=31;break;case 11:ri--;if(ri==0) ri=30;break;case 12:ri--;if(ri==0) ri=31;break;}write_nyr(8,ri);write_(0x80+0x08);write_ds(7,ri);}if(numfun==6){yue--;if(yue==-1)yue=12;write_nyr(5,yue);write_(0x80+0x05);write_ds(8,yue);}if(numfun==7){nian--;if(nian==-1)nian=99;leap=nian%4==0&&nian%100!=0;write_nyr(2,nian);write_(0x80+2);write_ds(9,nian);}}}}void set_alarm(){uchar ashi,afen,amiao;if(timeclk==0)//判断是否按下闹钟设定键{delay(5);//延时消抖if(timeclk==0){while(!timeclk);anumfun++;//按键次数加1if(anumfun==1){flag=1;write_(0x80+0x40+0x0a);write_(0x0f);}if(anumfun==2){flag=1;write_(0x80+0x40+0x07);write_(0x0f);}if(anumfun==3){flag=1;write_(0x80+0x40+0x04);write_(0x0f);}if(anumfun==4){flag=0;anumfun=0;}}}if(anumfun!=0){if(timeadd==0)//如果加功能键按下{delay(5);while(!timeadd);if(anumfun==1) //设定秒{amiao++;if(amiao==60)amiao=0;write_sfm(9,amiao);write_(0x80+0x40+9);write_ds(1,amiao);}if(anumfun==2){afen++;if(afen==60)afen=0;write_sfm(6,afen);write_(0x80+0x40+6);write_ds(3,afen);}if(anumfun==3){ashi++;if(ashi==24)ashi=0;write_sfm(3,ashi);write_(0x80+0x40+3);write_ds(5,ashi);}}}if(anumfun!=0){if(timesub==0){delay(5);while(!timesub);if(anumfun==1){amiao--;if(amiao==-1)amiao=59;write_sfm(9,amiao);write_(0x80+0x40+9);write_ds(1,amiao);}if(anumfun==2){afen--;if(afen==-1)afen=59;write_sfm(6,afen);write_(0x80+0x40+6);write_ds(3,afen);}if(anumfun==3){ashi--;if(ashi==-1)ashi=23;write_sfm(3,ashi);write_(0x80+0x40+3);write_ds(5,ashi);}}}}void init(){EA=1;//开总中断EX0=1;//开外部中断0IT0=1;//设定触发方式为负跳变沿有效lcden=0;//选通液晶显示屏ledrw=0;//设定液晶显示屏的读写方式为读write_(0x38);//设置液晶显示模式为16*2显示，5*7点阵，8位数据接口 write_(0x0c);//打开显示，并使光标不显示也不闪烁write_(0x06);//光标指针每次自动加1write_(1);//清屏write_(0x80);//送地址指针for(num=0;num<16;num++){write_date(table[num]);delay(5);}write_(0x80+0x40);//写到第二行for(num=0;num<11;num++){write_date(table1[num]);delay(5);}write_ds(0x0a,0x20);//开启时钟芯片振荡器write_ds(0x0b,0x26);//开启闹钟read_ds(0x0c);//读取时钟芯片c寄存器}void main(){init();while(1){keyscan();set_alarm();if(flag1==1)didi();if(flag==0){//读取时间miao=read_ds(0x00);fen=read_ds(0x02);shi=read_ds(0x04);yue=read_ds(0x08);ri=read_ds(0x07);nian=read_ds(0x09);week=read_ds(0x06);//写入液晶显示屏write_sfm(9,miao);write_sfm(6,fen);write_sfm(3,shi);write_nyr(2,nian);write_nyr(5,yue);write_nyr(8,ri);write_zhou(0x0f,week);}}}void exter() interrupt 0{flag1=1;read_ds(0x0c);//读时钟芯片c寄存器。