4*4鍵盤C51單片機程序

本程序已經(jīng)調(diào)試通過，4*4鍵盤接P1口數(shù)據(jù)從P2的8個發(fā)光二極管來表示，也可以接數(shù)碼管；只是為了能夠讀取鍵值而沒有接，如果接數(shù)碼管可以加一個查表顯示的模塊在switch語句中調(diào)用顯示程序； 

/*MCU:AT89S52*/ 

#include <reg52.h> 
#include <intrins.h> 
#define uchar unsigned char 

int key; 
int del; 
void Key_Scan(void); 

/************主程序*************/ 
void main(void) 
{  
void Key_Scan(void); 
void delay(int); 
while(1) 
{ 
   Key_Scan();  
   delay(2000); 
} 
} 
/********矩鍵查尋鍵值4*4程序******/ 
void Key_Scan(void) 
{ 
uchar readkey;    
uchar x_temp,y_temp; 
P1=0x0f; 
x_temp=P1&0x0f; 
if(x_temp==0x0f) goto keyout; 
P1=0xf0; 
y_temp=P1&0xf0; 
readkey=x_temp|y_temp; 
readkey=~readkey; 

switch(readkey) 
    { 
   case 0x11:key=0;P2=key; break; 
case 0x21:key=1;P2=key; break; 
case 0x41:key=2;P2=key; break; 
case 0x81:key=3;P2=key; break; 
case 0x12:key=4;P2=key; break; 
case 0x22:key=5;P2=key; break; 
case 0x42:key=6;P2=key; break; 
case 0x82:key=7;P2=key; break; 
case 0x14:key=8;P2=key; break; 
case 0x24:key=9;P2=key; break; 
case 0x44:key=10;P2=key;break; 
case 0x84:key=11;P2=key;break; 
case 0x18:key=12;P2=key;break; 
case 0x28:key=13;P2=key;break; 
case 0x48:key=14;P2=key;break; 
case 0x88:key=15;P2=key;break; 
default: key=16;P2=key;break; 
    } 

keyout:_nop_(); 
} 
/************延時程序*************/ 
void delay(del) 
{ 
for(del;del>0;del--);  
} 



參考鏈接：http://www.picavr.com/news/2008-08/8075.htm