#include <Keypad.h>

const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
//define the Symbols on the buttons of the keypads
char hexaKeys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'Y','0','N','S'}
};
byte rowPins[ROWS] = {7, 8, 9, 10}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {6, 5, 4, 3}; //connect to the column pinouts of the keypad
//initialize an instance of class NewKeypad
Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

char code[9];
int code_x=0;

void printCode() {
  for(int x=0; x=8; x++) {
    Serial.print(code[x]);
  }
}

void setup(){
  Serial.begin(9600);
}

void loop(){
  char customKey = customKeypad.getKey();
  if (customKey=="N"){
    Serial.println(customKey);
    code_x=0;
  }
  else if (customKey=="Y") {
    Serial.println(customKey);
    Serial.println("invio codice...");
    printCode();
  }
  else if (customKey) {
    Serial.println(customKey);
    code[code_x]=customKey;
    code_x++;
    printCode();
    if (code_x=9) {
      code_x=0;
    }
  }
}