1.点亮LED

#include "reg52.h"
#include "intrins.h"
typedef unsigned char u8;
typedef unsigned int  u16;
#define led P2
void delay(u16 i)
{
    while(i--);
}
void main()
{
	  u8 i=0;
	  led=0xfe;
	  delay(50000);
    while(1)
		{
			 for(i=0;i<3;i++) 	
			{
				led=_crol_(led,2);
				delay(50000);
			}
			for(i=0;i<3;i++) 	
			{
				led=_cror_(led,2);
				delay(50000);
			}
		}


}

2.继电器（接触器的触头比较大，承载能力强，通过它来实现弱电到强电的控制，控制对象是电器）

#include "reg52.h"
#include "intrins.h"
typedef unsigned char u8;
typedef unsigned int  u16;
sbit relay=P1^4;//
void delay(u16 i)
{
    while(i--);
}
void main()
{ 
	  relay=0;
    while(1)
		{
			 
		}


}

3.静态数码管。（主要是了解共阳共阴数码管数码的表示方法）共阴取反就是供阳~。

#include "reg52.h"
#include "intrins.h"
typedef unsigned char u8;
typedef unsigned int  u16;
u8 smgduan[16]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,ox77,0x7c,0x39,0x5e,0x79,0x71};;

void main()
{
	  P0=~smgduan[0];
    while(1)
		{
			 
		}


}

4.动态数码管。（38编译器

#include "reg52.h"
#include "intrins.h"
typedef unsigned char u8;
typedef unsigned int  u16;
u8 smgduan[16]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
sbit LSA=P2^2; //38ÒëÂëÆ÷
sbit LSB=P2^3;
sbit LSC=P2^4;
void delay(u16 i)
{
	
  while(i--);
}
	
void DigDisplay1()
{
	u8 i;
  for(i=0;i<8;i++)
	{
	    switch(i)
			{
				case 7:
					LSA=0;LSB=0;LSC=0;P0=smgduan[4];break;
				case 6:
					LSA=1;LSB=0;LSC=0;P0=smgduan[1];break;
				case 5:
					LSA=0;LSB=1;LSC=0;P0=smgduan[3];break;
				case 4:
					LSA=1;LSB=1;LSC=0;P0=smgduan[1];break;
				case 3:
					LSA=0;LSB=0;LSC=1;P0=smgduan[0];break;
				case 2:
					LSA=1;LSB=0;LSC=1;P0=smgduan[2];break;
				case 1:
					LSA=0;LSB=1;LSC=1;P0=smgduan[5];break;
				case 0:
					LSA=1;LSB=1;LSC=1;P0=smgduan[0];break;
			}		
			delay(50000);
			P0=0x00;//ÇåÁã
	}
}
void DigDisplay2()
{
	u8 i;
  for(i=0;i<8;i++)
	{
	    switch(i)
			{
				case 7:
					LSA=0;LSB=0;LSC=0;P0=smgduan[4];break;
				case 6:
					LSA=1;LSB=0;LSC=0;P0=smgduan[1];break;
				case 5:
					LSA=0;LSB=1;LSC=0;P0=smgduan[3];break;
				case 4:
					LSA=1;LSB=1;LSC=0;P0=smgduan[1];break;
				case 3:
					LSA=0;LSB=0;LSC=1;P0=smgduan[0];break;
				case 2:
					LSA=1;LSB=0;LSC=1;P0=smgduan[2];break;
				case 1:
					LSA=0;LSB=1;LSC=1;P0=smgduan[5];break;
				case 0:
					LSA=1;LSB=1;LSC=1;P0=smgduan[0];break;
			}		
			delay(100);
			P0=0x00;//ÇåÁã
	}
}
void main()
{
	DigDisplay1();
	
    while(1)
		{
DigDisplay2();
		}


}

的用处）