5.c

四位数码管显示 没1分钟进1位 是通过最原始的51单片机来实现的

#include <reg51.h>
#define unchar  unsigned char
sbit P2_7=P2^7; 
sbit P2_6=P2^6; 
sbit P2_5=P2^5; 
sbit P2_4=P2^4; 
extern unsigned  a=0;
 extern unsigned b=0;
 extern unsigned c=0;
 extern unsigned d=0;
 extern unsigned j=55;
unchar led_tab[]={0x28,0xeb,0x32,0xa2,0xe1,0xa4,0x24,0xea,0x20,0xa0};


void dataprocess(){	j=55;
                    if(a==10){b++;a=0;} else{a++;}
                    if(b==6){c++;b=0;} 
 				    if(c==10){d++;c=0;} 
					if(d==6){a++;d=0;} 
     }
  
void display(int m )

{
   P0=led_tab[m];
  }



void timer0(void) interrupt 1
{
  j--;
 TR0=0;
  TH0=-(20000/256);
  TL0=-(20000%256);
TR0=1;
  
  }



void delay(unsigned int k)
{
while(k--);
}

void main()
{  TMOD=0x01;
   TH0=-(20000/256);
   TL0=-(20000%256);
   EA=1;
   ET0=1;
   TR0=1;
   
   while(1)
        {
        P2_7=0;
        display(a);
        delay(20);
        P2_7=1;

         
        P2_6=0;
        display(b);
        delay(20);
		P2_6=1;

        
         P2_5=0;
         display(c);
         delay(20);
		 P2_5=1;
         
         P2_4=0;
         display(d);
         delay(20);
		 P2_4=1;
		 
 if(j==0)dataprocess();

        
   }
}