求大神帮我看看，哪里错了

单片机表现出来的，不会停两秒啊
#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char
uchar t,num;
uchar code table[]={0x3f,0x30,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};
sbit wela=P2^7;
sbit dula=P2^6;
void delay(uint z) ;
void main()
{ t=0;
num=0;
TMOD=0X01;
TH0=(65536-50000)/256;
TL0=(65536-50000)%256;
EA=1;
ET0=1;
TR0=1;
wela=1;
P0=0;
wela=0;
dula=1;
P0=0x3f;
dula=0;
while(1)
{
for(num=0;num<16;num++)
{
dula=1;
P0=table[num];
dula=0;
delay(100);
if(t==80) break;
}
}
}
void timer0() interrupt 1
{
TH0=(65536-50000)/256;
TL0=(65536-50000)%256;
t++;
}
void delay(uint z)
{
uint x,y;
for(x=1000;x>0;x--)
for(y=z;y>0;y--);
}