键盘基本--反转法.txt

这包括三个键盘扫描程序,对新手有很大的帮助

#include<reg51.h>
#define uchar unsigned char
#define uint  unsigned int
//********************************
uchar key1[16]={0xe7,0xeb,0xed,0xee,0xd7,0xdb,0xdd,0xde,0xb7,0xbb,0xbd,0xbe,0x77,0x7b,0x7d,0x7e};

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

void delay(void);
void key_scan(void);
void display(void);


void main()
{ 
   	P2=0x0f;
	P1=0x00;
   	EA=1;
   	EX0=1;
	IT0=1;
    while(1);
}

//中断函数 
void int0_srv (void) interrupt 0  using 0
{ 
  EX0=0;
  delay();
  if(INT0==0)
    key_scan();
  P2=0x0f;
  EX0=1;
 
}

//键盘扫描，反转法 
void key_scan(void)
{ 
    k=P2;
    P2=0xf0;
    k=k|P2;
    display(); 
}

// 显示字符 
void display(void)
{ 
   uchar i;
   if(k!=0xff)
    { 
      for(i=0;i<16;i++)
        if(k==key1[i])
	   break;
      P1=key[i];
	}
}

//延时 
void delay(void)   
{ 
  uint j;
  for(j=0;j<3000;j++);
}