定時器控制流水燈

#include<reg52.h>
#include<intrins.h>
#define uchar unsigned char
#define uint unsigned int
uchar code table[10] = {0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};
uchar code LED_W[8] = {0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f};
uchar temp,tt;
char num;
void main()
{
 TMOD=0x01;
 TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 EA=1;
 ET0=1;
 TR0=1;
 tt=0;
 num=0;
 temp=0xfe;
 P1=temp;
 P2=LED_W[num];
 P0=table[num];
 while(1)
 {
  if(tt==20)
  {
   tt=0;
   temp=_crol_(temp,1);
   P1=temp;
   if(num==7)
    num=-1;
   P2=LED_W[++num];
   P0=table[num];
  }
 }
}
void time() interrupt 1
{
    TH0=(65536-50000)/256;
 TL0=(65536-50000)%256;
 tt++;
}