add_smg.c

52单片机开发板的实例程序

#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char 
sbit a=P1^0;
sbit b=P1^1;
sbit c=P1^2;
/******************************
共阴数码管0——15译码表
****************************************/
uchar table[]={
          0x3f,0x06,0x5b,0x4f,0x66,
          0x6d,0x7d,0x07,0x7f,0x6f};
void delay(uint j)
{
	uchar i;
	for(;j>0;j--)
	for(i=110;i>0;i--);
}
void HC138(uchar i)
{
	a=i&0x01;
	b=i&0x02;
	c=i&0x04;
}
void display(uchar num)
{
	uchar ge,shi;
	shi=num/10;
	ge=num%10;
	P2=table[shi];
	HC138(1);
	delay(3);
	P2=table[ge];
	HC138(0);
	delay(3);
}
void main()
{
   uchar k,date=0;
   while(1)
   {
      for(k=0;k<250;k++)
       {
		 display(date);
       }
	   date++;
	   if(date>99)
	   date=0;

  }
}