c---klawiatura-1.5

#include <REGX52.H>

unsigned char key, key1;
unsigned char znak[] = {0xFE,0xFD,0xFB,0xF7};
void analiza (unsigned char x, unsigned char y)
  {
    if(x != y) P2 = x;
  }


void main(void)
  {
    while(1)
      {
        for(int i=0; i<4; i++)
          {
            P0 = znak[i]; //  1111  1110
            key1 = znak[i];
            key = P0; // odczyt
            analiza(key,key1);
          }

      }
  }