cs7-3.c

《手把手教你学单片机的C程序设计》及实验程序

#include <REG51.H>
unsigned char code SEG7[10]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};
int data globe_x;			
//-----------------------------------------------------------------
void add(void);			
void subb(void);		
void delay(unsigned int k);	
void display(void);
//----------------------------------------------------------
void main(void)		
{					
	while(1)			
	{ 				
	add();			
	display();
	subb();
	display();			
	if(globe_x>999) {globe_x=0;}	
	}					
}					
//----------------------------------------------------
void add(void)				
{					
globe_x =globe_x+3;		
}						
//---------------------------------------------------
void subb(void)			
{						
globe_x =globe_x-2;			
}						
//----------------------------------------------------
void delay(unsigned int k)
{					
unsigned int i,j;		
for(i=0;i<k;i++){			
for(j=0;j<121;j++)			
{;}}					
}	
//------------------------------------------------------	
void display(void)			
{
unsigned char i;	
for(i=0;i<250;i++)	
		{			
		P0= SEG7[globe_x /100];
		P2=0xfb;				
		delay(1);					
		P0= SEG7[(globe_x %100)/10];	
		P2=0xfd;					
		delay(1);				
		P0= SEG7[globe_x%10];	
		P2=0xfe;				
		delay(1);				
		}
}