keyboard.c

来自「很有用的关于msp430单片机的很多很好的源程序」· C语言 代码 · 共 56 行

#include  <msp430x13x.h>
extern unsigned char keyFlag,keyvalue,keynewvalue,keyoldvalue,keynumber;
void keyscan(void)
{

   if( keyFlag==0)
   {   
       keynewvalue=P3IN&0xff;
       
       if(keynewvalue==keyoldvalue)
       {
          keynumber+=1;
       }
       else
       {
          keyoldvalue=keynewvalue;
          keynumber=0;
       }
       if(keynumber==40)
       {
           keynumber=0;
           switch(keynewvalue)
           {
               case 0x1:
                    keyvalue=1;
                    keyFlag=1;
                    break;
               case 0x2:        
                    keyvalue=3;
                    keyFlag=1;        
                    break;

               case 0x4:
                    keyvalue=4;
                    keyFlag=1; 
                    break;
               case 0x8:        
                    keyvalue=2;
                    keyFlag=1;        
                    break;
               case 0x10:
                    keyvalue=5;
                    keyFlag=1; 
                    break;
               case 0x20:        
                    keyvalue=6; 
                    keyFlag=1;       
                    break;
            default:
                    break;              
           } 
       }
   }
}
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