key.c

用51单片机实现的在屏幕上显视文字,外接一颗MT230OSDIC

#include "golbal.h"

WORD data KeyTime;

BYTE xdata AD3Level;

BYTE KeyCode,OldKeyCode,KeyRepeat;
BYTE idata KeyDelayCount;

BYTE data ModePressCount;

void KeyPress()
{
   BYTE idata KBuf1, TempKey;

   KBuf1 = AD3Level;

   if(KBuf1 < KADC3_1)
   		{
       		KBuf1=Mode_Key;
    		}
   else if(KBuf1 < KADC3_2)
   		{
      			KBuf1=Up_Key;
   		}
   else if(KBuf1 < KADC3_3)
   		{
      			KBuf1=Down_Key;
   		}
   else if(KBuf1 < KADC3_4)
   		{
      			KBuf1=Rotate_Key;
   		}
   else
   		{
      		KBuf1=No_Key;
   		}
   
   TempKey=KBuf1;

   if(OldKeyCode==TempKey)//key repeat
   	{
   	    if(TempKey!=No_Key)
   	    {
      		if(KeyRepeat<255)
      		{
         		KeyRepeat++;
      		}
           }
      	    if(KeyRepeat<KEY_ACC_COUNT)
      		{
         		KeyCode=No_Key;
      		}
      	   else
      		{
         		KeyCode=OldKeyCode=TempKey;
      		}
   	    
   	}
   else  // key press first time
   	{
      		KeyRepeat=0;
      		KeyCode=OldKeyCode=TempKey;
   	}	
}