为什么有一个数码管不亮？？？？

#include

#include
***it dula=P2^6;
***it wela=P2^7;
#define uchar unsigned char
#define uint  unsigned  int
#define  dearpot  P0
uchar code temap[]={0x3F,0x06,0x5B,0x4F,
                           0x66,0x6D,0x7D,0x07,
0x7F,0x6F,0x77,0x7C,
0x39,0x5E,0x79,0x71,
   0};
uchar code  weiz[]={0xfe,0xfd,0xfb,0x7f,0xef,0xdf};
uchar TempData[8];
void delay (uint z);
void display(uchar tt,uchar aa);
uchar cc;
uint num;
   void exmerpt0() interrupt 1
   {
   TH0=(65536-50000)/256;
      TL0=(65536-50000)%256;
cc++;
   }
void main()
{
uint num=9999;
  TMOD=0X01;
  TH0=(65536-50000)/256;
  TL0=(65536-50000)%256;
  EA=1;
  TR0=1;
  ET0=1;

while(1)

{
   if(cc==10)
   {
cc=0;
   if(num>0)
   {
   num--;
   }
   if(num==0)
   {
   num=9999;
   }
   }

TempData[0]=temap[num/1000];
TempData[1]=temap[(num%1000)/100];
TempData[2]=temap[((num%1000)%100)/10];
TempData[3]=temap[((num%1000)%100)%10];
      display(2,4);

}
}
  void delay (uint z)
  {
  uint x,y;
  for(x=z;x>0;x--)
  for(y=110;y>0;y--);
  }
   void display(uchar tt,uchar aa)
   {
   uchar i;
   for(i=0;i    {
      dearpot=0;
      dula=1;
      dula=0;

dula=1;
      dearpot =TempData[i];
      dula=0;

dearpot=0xff;
      wela=1;
      dearpot=weiz[i+tt];
      wela=0;

      delay(2);
   }
   }