# include <reg51.h>
# define led P1       
# define Ton 40        //基準(zhǔn)脈寬0.04ms 
# define true 1

code unsigned char stop[3] _at_ 0x3B;   //Mon51用,絕對(duì)地址引用
unsigned char LEDflag = 0;    //全局變量,最大255,保存T0中斷次數(shù)
static unsigned char ledon[8] = {0x7f,0xbf,0xdf,0xef,0xf7,0xfb,0xfd,0xfe}; 

void timer_init()    //定時(shí)器初始化
{
 	TMOD = 0x02;    //T0 方式2,8位自動(dòng)載入
 	TH0 =  256 - Ton;   //T0初始值
	TL0 =  256 - Ton;   //重載值
 	TR0 = true;     //啟動(dòng)T0
 	ET0 = true;     //開(kāi)T0,T1中斷 
 	EA = true;     //全局中斷允許
}

void time0_int() interrupt 1 using 3  //T0中斷函數(shù),中斷1,使用工作組3 
{
 	LEDflag++;      //修改LEDflag
}


led_show4()
{
 	unsigned char i = 0,j = 0;  // i初始化
 	for(j = 0;j<=7;j++)
	{
 		i = 0;       // i初始化 
 		while(i!=255)     // 由暗變亮
 	   {
    		if(LEDflag == 0)  // 點(diǎn)亮
  			{
  				led = ledon[j];
  			}
  			if(LEDflag == i)  // 熄滅
  			{
 				 led = 0xff;
 			 }
 			 if(LEDflag == 255)    //修改變量
 			 {
  				 i++;      
 			 }
 		} 
	}
 
	for(j=7;j>=0;j--)
	{ 
 		i = 0;       // i初始化    
		 while(i!=255)     // 由亮變暗
 		{
 			 if(LEDflag == 0)  // 熄滅
 			 {
  				led = 0xff;
 			 }
  		 	 if(LEDflag == i)  // 點(diǎn)亮
  			{
 				 led = ledon[j];
 			 }
 			 if(LEDflag == 255)  //修改變量
 			 {
  				 i++;
 			 }
 		}   
 	}  
}
 
void main()
{ 
	 timer_init();
  	 while(1)
 	{
  
 		 led_show4();
 
 	}
}