34key.c

用单片机控制4×8按键的详细例子程序。和大家共享

#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() //按键扫描子程序
{
 P1=0xFF;
 P1_3=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=1;break;
   case 0xB0:
    key=2;break;
   case 0xD0:
    key=3;break;
   }
   Dispaly(key);
  }
 }

 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=4;break;
   case 0xB0:
    key=5;break;
   case 0xD0:
    key=6;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=7;break;
   case 0xB0:
    key=8;break;
   case 0xD0:
    key=9;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=14;break;
   case 0xB0:
    key=0;break;
   case 0xD0:
    key=15;break;
   }
   Dispaly(key);
  }
 }
}

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

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