按键调节数码管的显示数字(百、十、个可单独调节)

void main()
{ init();
nuቤተ መጻሕፍቲ ባይዱ=521;
while(1)
{ keyscan();
if(i>=20)
{ i=0;
num--;
}
display(num);
}
}
void init() //定时器初始化
{ TMOD=0X01;
TH0=(65536-50000)/256;
TL0=(65536-50000)%256;
bai=num/100;
shi=num%100/10;
ge=num%10;
dula=1;
P0=table[bai];
dula=0;
P0=0xff;
wela=1;
P0=0xfe;
wela=0;
delay(2);
dula=1;
P0=table[shi];
dula=0;
P0=0xff;
wela=1;
P0=0xfd;
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};
void delay(uchar x);
void init();
void keyscan();
void display(uint num);
void delay(uchar x);
/
#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char
sbit dula=P2^6; //数码管段选
sbit wela=P2^7; //数码管位选
sbit en=P3^4; //确定要调节的位置（个、十、百）
sbit jia=P3^5;//加一
TR0=0;
j++;
if(j==4)
j=0;
switch(j)
{ case 0:{led=1;led1=1;led2=1;};break;
case 1: {led=0;led1=1;led2=1;};break;
case 2:{ led=1;led1=0;};break;
case 3:{led=1;led1=1;led2=0;};break;
wela=0;
delay(2);
dula=1;
P0=table[ge];
dula=0;
P0=0xff;
wela=1;
P0=0xfb;
wela=0;
delay(2);
}
void delay(uchar x)//延时
{ uchar i,j;
for(i=x;i>0;i--)
for(j=110;j>0;j--);
}while(!jia);
}
display(num);
}
if(m==0)
{ delay(5);
if(m==0)
TR0=1;
while(!m);
}
}
void display(uint num)//显示
{ uchar bai,shi,ge;
//num=num1+num;
if(num==1000)
num=0;
EA=1;
ET0=1;
TR0=1;
}
void time0()interrupt 1//中断函数
{ TH0=(65536-50000)/256;
TL0=(65536-50000)%256;
i++;
}
void keyscan() //按键扫描
{ if(en==0)
{delay(5);
if(en==0)
{ while(!en);
}
}
}
if(jia==0)
{delay(5);
if(jia==0)
{ l++;
if(l==2)
l=1;
switch(j)
{ case 1:{num+=l;};break;
case 2:{num+=l*10;};break;
case 3:{num+=l*100;};break;
//default:break;
sbit m=P3^6; //确定。时间调好后，按这个键开始计数
sbit led=P1^0; //调节个位时led亮
sbit led1=P1^3;//调节十位时led1亮
sbit led2=P1^5;//调节百位时led1亮
uint num,i,j,l,num1;
uchar code table[]={0x3f,0x06,0x5b,0x4f,
}