/*  4x4矩陣鍵盤的掃描程序
按相應的按鍵，數(shù)碼管顯示相應的數(shù)字，星號鍵和井號鍵分別顯示為E和F
*********************************
  Create by:左秀龍  
  support:
  Tel:0755-82879296
  email: cutedesign@tom.com
  Date: 2005/06/23
*********************************
測試通過*/ 
#include


unsigned char code table[]={0xC0,0xF9,0xA4,0xB0,0x99, //0~4
       											0x92,0x82,0xF8,0x80,0x90, //5~9
      											0x88,0x83,0xA7,0xA1,0x86,0x8E}; //A~F

void KeyScan();
void delay10ms(unsigned char time);
void Dispaly  (unsigned char k);

unsigned char key,temp;

void main() //主程序
{
 while(1)
 {
  KeyScan();
 }
}

void KeyScan()   //按鍵掃描子程序，先掃描列，再掃描行。
{
 P1=0xFF;
 P1_3=0;
 temp=P1;
 temp&=0xF0;  
 if(temp !=0xF0) //檢查有鍵按下
 {
  delay10ms(1);  //延時
  temp=P1;
  temp&=0xF0;
  if(temp !=0xF0)//去抖動，再次檢查有鍵按下
  {
   temp=P1;
   temp&=0xF0;

   switch(temp)  //計算鍵值
   {
   case 0x70:
    key=1;break;
   case 0xB0:
    key=2;break;
   case 0xD0:
    key=3;break;
   case 0xE0:
    key=4;break;    
   }
   Dispaly(key); //顯示按鍵鍵值
  }
 }

 P1=0xFF;
 P1_2=0;
 temp=P1;
 temp&=0xF0;
 if(temp !=0xF0)
 {
  delay10ms(1);
  temp=P1;
  temp&=0xF0;
  if(temp !=0xF0)
  {
   temp=P1;
   temp&=0xF0;

   switch(temp)
   {
   case 0x70:
    key=5;break;
   case 0xB0:
    key=6;break;
   case 0xD0:
    key=7;break;
   case 0xE0:
    key=8;break; 
   }
   Dispaly(key);
  }
 }

 P1=0xFF;
 P1_1=0;
 temp=P1;
 temp&=0xF0;
 if(temp !=0xF0)
 {
  delay10ms(1);
  temp=P1;
  temp&=0xF0;
  if(temp !=0xF0)
  {
   temp=P1;
   temp&=0xF0;

   switch(temp)
   {
   case 0x70:
    key=9;break;
   case 0xB0:
    key=10;break;
   case 0xD0:
    key=11;break;
   case 0xE0:
    key=12;break; 
   }
   Dispaly(key);
  }
 }

 P1=0xFF;
 P1_0=0;
 temp=P1;
 temp&=0xF0;
 if(temp !=0xF0)
 {
  delay10ms(1);
  temp=P1;
  temp&=0xF0;
  if(temp !=0xF0)
  {
   temp=P1;
   temp&=0xF0;

   switch(temp)
   {
   case 0x70:
    key=13;break;
   case 0xB0:
    key=14;break;
   case 0xD0:
    key=15;break;
   case 0xE0:
    key=0;break; 
   }
   Dispaly(key);
  }
 }
}

//延時程序
void delay10ms(unsigned char time)
{
 unsigned char a,b,c;
 for(a=0;a<time;a++)  
  for(b=0;b<10;b++)
   for(c=0;c<120;c++);
}

//顯示程序
void Dispaly(unsigned char k) 
{
 P0=table[k];        //段選
 P2_1=0;             //位選
}