sckey.c

基于4*4距阵式键盘的键盘扫描子程序,去抖.

#include <c8051f020.h>
#include"ks0108.h"
#include"PCF8563.H"
#include "ZiKu.h"  


/*#define arrangekey P3	//P3口低五位接行线
#define rowkey P1		//P14—P16接列线*/

extern void Delay1ms(unsigned char T);


unsigned char keyscan(void)
{
   unsigned char scancode, tmpcode;
   P3 &= 0xe0;	  //行端口送全0
   if((P1&0x70)!= 0x70)
   {
       Delay1ms(10);
	   if((P1&0x70)!= 0x70)
	   {   
	   		//scancoderow = P1;
	        //scancoderow &= 0x70;
		   scancode = 0xfe;
           while ((scancode&0x20) != 0)
		   {
				P3 |=(scancode | 0x1f);

			    if((P1 & 0x70) != 0x70)		 //本行有键按下
		        {
		        	tmpcode = ( P1&0x70 ) | 0x8f;
			    	return(~scancode) + (~tmpcode);
		        }
		        else
					scancode=(scancode<<1) | 0x01;	   //行扫描码左移一位
		   	}
	    }
	}
	return(0);      
}

void KeyIn(void)
{
	unsigned char key;
    while (1)
    {
        key = keyscan();
        switch (key)
        {
   	        case 0x21:
	           DispBmp(screen);
		       break;
	        case 0x41:
	           TestI2C();
		    break;
        }
      }
}