单片机实验1提示

#include<8052.h>

#define LSA P1_5
#define LSB P1_6
#define LSC P1_7

void EXint_Init(void);
void Delayms(unsigned int);
void Down2Up(int);		        
void Up2Down(int);				
void EXINT0() __interrupt 0;
void EXINT1() __interrupt 2;

void main()
{
	EXint_Init();	
	LSA=0;
	LSB=0;
	LSC=0;
	while(1)
	{
		P0 = 0x55;
	}                         
}

void EXint_Init()              
{
	IT0=1;                     
//	IT1=0;                     
//	IPH=0x40;                   
//	PX1=1;                     
	EA=1;                       
	EX0=1;                      
//	EX1=1;                      
}


void Delayms(unsigned int xms)
{
	unsigned int i,j;
	for(i = xms;i > 0;i--)
	{
		for (j = 110;j > 0;j--);
	}
}

void EXINT0() __interrupt 0     	
{
	Down2Up(3);					
}

void EXINT1() __interrupt 2       
{
	Up2Down(3);					
}

void Down2Up(int x) 				 
{	
	int i, j;
	unsigned char sel=0xfe;						
	for(i=0;i<x;i++)			
	{	
		for(j=0;j<8;j++)		
		{	
			P0 = sel;
			Delayms(250);		
			sel =sel<<1; 	
		}
		sel=0xfe;						
	}
}

void Up2Down(int x) 		
{	
	int i, j;
	unsigned char sel=0x7f;								
	for(i=0;i<x;i++)			
	{	
		for(j=0;j<8;j++)		
		{	
			P0 = sel;
			Delayms(250);	
			sel=sel>>1; 	
		}
		sel=0x7f;						
	}
}