矩阵键盘的扫描检测例程

mogyz · 发表于 2020-2-15 15:17:22

#include<reg51.h>
sbit beep=P2^3;
sbit dula=P2^0;       //段选信号的锁存器控制
sbit wela=P2^1;       //位选信号的锁存器控制
sbit cs88=P2^2;       //点阵管的锁存器控制       cs88=0;//关点阵管
sbit led_en=P2^5;
      unsigned char i=100;
unsigned char j,k,temp,key;
void delay(unsigned char i)
{
  for(j=i;j>0;j--)
for(k=125;k>0;k--);
}
unsigned char code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,
                     0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
display(unsigned char num)
{
      P0=table[num];
      dula=1;
      dula=0;
      P0=0x00;
      wela=1;
      wela=0;
}
void main()
{
   led_en=0;
cs88=1;
P0=0xff;
cs88=0; //关点阵管
  dula=0;
  wela=0;
  while(1)
  {
P3=0xfe;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
   delay(10);
   if(temp!=0xf0)
   {
      temp=P3;
      switch(temp)
      {
      case 0xee:
            key=0;
            break;

      case 0xde:
            key=1;
            break;

      case 0xbe:
            key=2;
            break;

      case 0x7e:
            key=3;
            break;
      }
      while(temp!=0xf0)
      {
         temp=P3;
         temp=temp&0xf0;
         beep=0;
      }
      beep=1;
      display(key);
      P1=0xfe;
   }
}
P3=0xfd;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
   delay(10);

if(temp!=0xf0)
   {
      temp=P3;
      switch(temp)
      {
      case 0xed:
            key=4;
            break;

      case 0xdd:
            key=5;
            break;

      case 0xbd:
            key=6;
            break;

      case 0x7d:
            key=7;
            break;
      }
      while(temp!=0xf0)
      {
         temp=P3;
         temp=temp&0xf0;
         beep=0;
      }
      beep=1;
      display(key);
   }
   }
P3=0xfb;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
   delay(10);
   if(temp!=0xf0)
   {
      temp=P3;
      switch(temp)
      {
      case 0xeb:
            key=8;
            break;

      case 0xdb:
            key=9;
            break;

      case 0xbb:
            key=10;
            break;

      case 0x7b:
            key=11;
            break;
      }
      while(temp!=0xf0)
      {
         temp=P3;
         temp=temp&0xf0;
         beep=0;
      }
      beep=1;
      display(key);
   }
   }
P3=0xf7;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
   delay(10);
   if(temp!=0xf0)
   {
      temp=P3;
      switch(temp)
      {
      case 0xe7:
            key=12;
            break;

      case 0xd7:
            key=13;
            break;

      case 0xb7:
            key=14;
            break;

      case 0x77:
            key=15;
            break;
      }
      while(temp!=0xf0)
      {
         temp=P3;
         temp=temp&0xf0;
         beep=0;
      }
      beep=1;
      display(key);
   }
}
  }
}