Keymatrix polling Function

gistfile1.ino

static void scanKeys(){
  //iterate over columns
  for(int currentColumn = 0; currentColumn < COL_COUNT; currentColumn ++){
    digitalWrite(cols[currentColumn],HIGH);

    //scan rows
    for(int y = 0; y < ROW_COUNT; y++){
      Key* key = keyMatrix[currentColumn][y];
      if(key != NOKEY){

        int state = digitalRead(rows[y]);
        if((state == HIGH && !key->pressed) || (state == LOW && key->pressed)){
          //The toggleKey function actually does the debouncing.
          //It returns true if the state really changed.
          //And false otherwise
          if(toggleKey(key)){
            keyChanged = true;
          }
        }

        //collect report data
        if(key->pressed){
          if(pressedKeyIndex < MAX_KEYS_PRESSED){
            pressedKeys[pressedKeyIndex] = key;
            pressedKeyIndex++;
          } 
        }
      }
    }
    digitalWrite(cols[currentColumn],LOW);
  }
}