w7.c

C51D单片机4*4键盘试验

#include<reg51.h>
unsigned char keyv;
unsigned char code table[]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,0x88,0x83,0xC6,0xA1,0x86,0x8E,0xff}; //字形码）
void delay1ms(unsigned int t)
{ unsigned int i,j;
   for(i=0;i<t;i++)
    for(j=0;j<120;j++);
}

   void keyscan() //按键扫描子程序
{ unsigned char temp,scode;
    scode=0xfe;
    P1=scode;
	temp=P1;
	temp&=0xf0;
if(temp!=0xf0)
   {delay1ms(10);
    temp=P1;
    temp&=0xf0;
     if(temp!=0xf0)
   {temp=P1;
       temp&=0xF0;
    switch(temp)
          {case 0xe0: keyv=0;break;
           case 0xd0: keyv=1;break;
           case 0xb0: keyv=2;break;
           case 0x70: keyv=3;break;
           }
   }
   }
scode=0xfd;
     P1=scode;
 	 temp=P1;
	 temp&=0xf0;
if(temp!=0xf0)
   {delay1ms(10);
    temp=P1;
    temp&=0xf0;
     if(temp!=0xf0)
   {temp=P1;
       temp&=0xF0;
    switch(temp)
          {case 0xe0: keyv=4;break;
           case 0xd0: keyv=5;break;
           case 0xb0: keyv=6;break;
           case 0x70: keyv=7;break;
           }
    }
    } 
scode=0xfb;
     P1=scode;
temp=P1;
temp&=0xf0;
if(temp!=0xf0)
   {delay1ms(10);
    temp=P1;
    temp&=0xf0;
     if(temp!=0xf0)
   {temp=P1;
       temp&=0xF0;
    switch(temp)
          {case 0xe0: keyv=8;break;
           case 0xd0: keyv=9;break;
           case 0xb0: keyv=10;break;
           case 0x70: keyv=11;break;
           }
    }
    } 
scode=0xf7;
     P1=scode;
temp=P1;
temp&=0xf0;
if(temp!=0xf0)
   {delay1ms(10);
    temp=P1;
    temp&=0xf0;
     if(temp!=0xf0)
   {temp=P1;
       temp&=0xF0;
    switch(temp)
          {case 0xe0: keyv=12;break;
           case 0xd0: keyv=13;break;
           case 0xb0: keyv=14;break;
           case 0x70: keyv=15;break;
           }
    }
    } 
    }
   
void display()
{ P0=table[keyv];
  P2=0;
}
void main()
{keyv=16;
   while(1)
{ keyscan();
    display();
}
}