iar6-6.c

手把手教你学AVR单片机C程序设计实验程序

#include<iom16.h>			
#define uchar unsigned char	
#define uint unsigned int

__flash uchar SKEY[16]={10,11,12,13,3,6,9,14,2,5,8,0,1,4,7,15};		
__flash uchar act[4]={0xfe,0xfd,0xfb,0xf7};

__flash uchar SEG7[16]={0x3f,0x06,0x5b,0x4f,0x66,
0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};

void delay_ms(uint k)			
{
    uint i,j;
    for(i=0;i<k;i++)
    {
       for(j=0;j<1140;j++);
    }
}
//=============================

uchar scan_key(void)			
{					
uchar i,j,in,ini,inj;			
uchar find=0;					
	for(i=0;i<4;i++)			
	{					
	PORTB=act[i];				
	delay_ms(10);				
	in=PINB;					
	in=in>>4;				
	in=in|0xf0;				
		for(j=0;j<4;j++)		
		{				
		  if(act[j]==in)		
		  {find=1;			
		  inj=j;ini=i;			
		  }					
		}					
	}						
	if(find==0)return 16;		
	return (ini*4+inj);			
}						
//=============================

void main(void)		
{					
uchar c,key_value;	
DDRA=0xff;		
DDRC=0xff;		
DDRB=0x0f;		
PORTA=0x00;		
PORTC=0xff;		
PORTB=0xff;	
   while(1)		
   {	
   c=scan_key();			
   if(c!=16)key_value=SKEY[c];	
   PORTA=SEG7[key_value];		
   PORTC=0xfe;		
   delay_ms(1);	
   }			
}