99table.c

开始时

#include <AT89X51.H> 
  
unsigned char code dispcode[]={0x3f,0x06,0x5b,0x4f, 
                               0x66,0x6d,0x7d,0x07, 
                               0x7f,0x6f,0x77,0x7c, 
                               0x39,0x5e,0x79,0x71,0x00}; 
unsigned char second; 
unsigned char keycnt; 
unsigned int tcnt; 
  
void main(void) 
{ 
  unsigned char i,j; 
  
  TMOD=0x02; 
  ET0=1; 
  EA=1; 
  second=0; 
  P0=dispcode[second/10]; 
  P2=dispcode[second%10]; 
  while(1) 
    { 
      if(P3_5==0) 
        { 
          for(i=20;i>0;i--) 
          for(j=248;j>0;j--); 
          if(P3_5==0) 
            { 
              keycnt++; 
              switch(keycnt) 
                { 
                  case 1: 
                    TH0=0x06; 
                    TL0=0x06; 
                    TR0=1; 
                    break; 
                  case 2: 
                    TR0=0; 
                    break; 
                  case 3: 
                    keycnt=0; 
                    second=0; 
                    P0=dispcode[second/10]; 
                    P2=dispcode[second%10]; 
                    break; 
                } 
              while(P3_5==0); 
            } 
        } 
    } 
} 
  
void t0(void) interrupt 1 using 0 
{ 
  tcnt++; 
  if(tcnt==400) 
    { 
      tcnt=0; 
      second++; 
      if(second==100) 
        { 
          second=0; 
        } 
      P0=dispcode[second/10]; 
      P2=dispcode[second%10]; 
    } 
}