keyboard_driver.c

单片机 mega16L 电池放电器源码

#include <iom8v.h>
#include <macros.h>
#include "discharge.h"
 unsigned char key_old;
 unsigned char key_time;
unsigned int key(unsigned char a)
{
 unsigned char pb=0;
 if(a==0)
 {  
    delay_nms(1);
    pb=(~PINB)&0x39;
	a=(pb>>2)|(pb&0x01); 
	if(a==key_old)
	  {
	    key_time++;
		 if(key_time==20)
		   {a|=0x10;key_old=a;key_time=0;return a;}
		 else
		return 0;
	}
	  else 
	    {
		  if(a==(key_old&~0x10)){return 0;}
		 else  key_old=a;key_time=0;return a;
		}
 }
 return a;
}