这是一个显示时钟的c语言程序，但是不知道怎么设置闹钟，求高手指教！！！（蜂鸣器接的是P2^3引脚）
#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char
uchar a,miao,shi,fen,temp,key1n;
#define yh 0x80 //第一行的初始位置
#define er 0x80+0x40 //第二行初始位置
sbit dula=P2^6;
sbit wela=P2^7;
sbit wr=P1^1;
sbit rs=P1^0;
sbit en=P2^5;
sbit SCLK=P2^1;
sbit IO=P2^0;
sbit RST=P2^4;
sbit ACC0=ACC^0;
sbit ACC7=ACC^7;
sbit key=P3^7;
sbit key1=P3^0;
sbit key2=P3^1;
sbit key3=P3^2;
uchar code tab1[]=" 2012-08-10 FRI";
uchar code tab2[]=" : : ";
void delay(uint xms)//延时函数 例：delay(5)大约延时5ms
{
uint x,y;
for(x=xms;x>0;x--)
for(y=110;y>0;y--);
}
/******************液晶写入************************/
void write_1602com(uchar com)//液晶写入指令函数
{
rs=0;//置为写入命令
P0=com;//送入数据
delay(1);
en=1;//拉高使能端
delay(1);
en=0;//完成高脉冲
}
void write_1602dat(uchar date)
{
rs=1;//置为写入数据
P0=date;//送入数据
delay(1);
en=1;
delay(1);
en=0;
}
/*********************over***********************/
/********************ds1302****************************/
void write_byte(uchar date)
{
ACC=date;
RST=1;
for(a=8;a>0;a--)
{
IO=ACC0;
SCLK=0;
SCLK=1;
ACC=ACC>>1;
}
}
uchar read_byte()
{
RST=1;
for(a=8;a>0;a--)
{
ACC7=IO;
SCLK=1;
SCLK=0;
ACC=ACC>>1;
}
return (ACC);
}
void write_1302(uchar add,uchar dat)
{
RST=0;
SCLK=0;
RST=1;
write_byte(add);
write_byte(dat);
SCLK=1;
RST=0;
}
uchar read_1302(uchar add)
{
uchar temp;
RST=0;
SCLK=0;
RST=1;
write_byte(add);
temp=read_byte();
SCLK=1;
RST=0;
return(temp);
}
uchar BCD_Decimal(uchar bcd)
{
uchar Decimal;
Decimal=bcd>>4;
return(Decimal=Decimal*10+(bcd&=0x0F));
}
void ds1302_init()
{
RST=0;
SCLK=0;
write_1302(0x80,miao|0x00);//允许写
}
void write_sfm(uchar add,uchar dat)//写时分秒
{
uchar gw,sw;
gw=dat%10;
sw=dat/10;
write_1602com(er+add);
write_1602dat(0x30+sw);
write_1602dat(0x30+gw);
}
void lcd_init()//液晶初始化函数
{
wr=0;
write_1602com(0x38);//设置液晶工作模式
write_1602com(0x0c);//开显示不显示光标
write_1602com(0x06);//整屏不移动，指针加一
write_1602com(0x01);
write_1602com(yh);//第一行字符写入的位置
for(a=0;a<15;a++)
{
write_1602dat(tab1[a]);
}
write_1602com(er);
for(a=0;a<12;a++)
{
write_1602dat(tab2[a]);
}
}
void keyscan()
{
key=0;
if(key1==0)//key1为功能键
{
delay(5);
if(key1==0)
{
while(!key1);
key1n++;
if(key1n==5)
key1n=1;
switch(key1n)
{
case 1: TR0=0;//关闭定时器
write_1602com(er+0x0b);//写入光标位置
write_1602com(0x0f);//设置光标为闪烁
temp=(miao)/10*16+(miao)%10;
write_1302(0x8e,0x00);
write_1302(0x80,0x80|temp);//miao
write_1302(0x8e,0x80);
break;
case 2: write_1602com(er+8);//fen
break;
case 3: write_1602com(er+5);//shi
break;
case 4:
write_1602com(0x0c);//设置光标不闪烁
TR0=1;//打开定时器
temp=(miao)/10*16+(miao)%10;
write_1302(0x8e,0x00);
write_1302(0x80,0x00|temp);//miao
write_1302(0x8e,0x80);
break;
}
}
}
if(key1n!=0)//当key1按下以下。再按一下键才有效
{
if(key2==0) //上调键
{
delay(5);
if(key2==0)
{
while(!key2);
switch(key1n)
{
case 1:miao++;
if(miao==60)
miao=0;
write_sfm(0x0a,miao);//写入新的秒数
temp=(miao)/10*16+(miao)%10;
write_1302(0x8e,0x00);
write_1302(0x80,0x80|temp);
write_1302(0x8e,0x80);
write_1602com(er+0x0b);//因为设置液晶的模式是写入数据后，指针自动加一，在这里是写回原来的位置
break;
case 2:fen++;
if(fen==60)
fen=0;
write_sfm(0x07,fen);
temp=(fen)/10*16+(fen)%10;
write_1302(0x8e,0x00);
write_1302(0x82,temp);
write_1302(0x8e,0x80);
write_1602com(er+8);
break;
case 3:shi++;
if(shi==24)
shi=0;
write_sfm(4,shi);
temp=(shi)/10*16+(shi)%10;
write_1302(0x8e,0x00);
write_1302(0x84,temp);
write_1302(0x8e,0x80);
write_1602com(er+5);
break;
}
}
}
if(key3==0)
{
delay(5);
if(key3==0)
{
while(!key3);
switch(key1n)
{
case 1:miao--;
if(miao==-1)
miao=59;
write_sfm(0x0a,miao);//写入新的秒数
write_1602com(er+0x0b);//因为设置液晶的模式是写入数据后，指针自动加一，在这里是写回原来的位置
break;
case 2:fen--;
if(fen==-1)
fen=59;
write_sfm(7,fen);
temp=(fen)/10*16+(fen)%10;
write_1302(0x8e,0x00);
write_1302(0x82,temp);
write_1302(0x8e,0x80);
write_1602com(er+8);
break;
case 3:shi--;
if(shi==-1)
shi=23;
write_sfm(4,shi);
temp=(shi)/10*16+(shi)%10;
write_1302(0x8e,0x00);
write_1302(0x84,temp);
write_1302(0x8e,0x80);
write_1602com(er+5);
break;
}
}
}
}
}
void init()
{
TMOD=0x11;
TH0=0;
TL0=0;
EA=1;
ET0=1;
TR0=1;
}
void cmg(void)//数码管锁存函数
{
dula=1;
P0=0x00;
dula=0;
wela=1;
P0=0x00;
wela=0;
}
void main()
{
cmg();//数码管锁存
lcd_init();
ds1302_init();
init();
while(1)
{
keyscan();
}
}
void timer0() interrupt 1
{
miao=BCD_Decimal(read_1302(0x81));
fen=BCD_Decimal(read_1302(0x83));
shi=BCD_Decimal(read_1302(0x85));
write_sfm(10,miao);
write_sfm(7,fen);
write_sfm(4,shi);
}
解决办法：
加一个判断 加一个标志FLAG
if（（shi == 0）&& （fen == 0））
{
FLAG = 1;
}
else ();
最后主程序里 加判断
if（FLAG == 1）
{
打开 蜂鸣器电源 ,响一分钟 ；
}
（用不同的标志来识别不同的时间，从而实现闹钟功能）
畅学电子
