count-ontime.c

来自「34个单片机的设计资料」· C语言 代码 · 共 43 行

#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 tcount; 
  
void main(void) 
{ 
  TMOD=0x01; 
  TH0=(65536-50000)/256; 
  TL0=(65536-50000)%256; 
  TR0=1; 
  tcount=0; 
  second=0; 
  P0=dispcode[second/10]; 
  P2=dispcode[second%10]; 
  while(1) 
    { 
      if(TF0==1) 
        { 
          tcount++; 
          if(tcount==20) 
            { 
              tcount=0; 
              second++; 
              if(second==60) 
                { 
                  second=0; 
                } 
              P0=dispcode[second/10]; 
              P2=dispcode[second%10];              
            } 
          TF0=0; 
          TH0=(65536-50000)/256; 
          TL0=(65536-50000)%256; 
        } 
    } 
}