#include <Keypad.h>

int LED0 = 13;

const byte ROWS = 3;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'A', 'B', 'C', 'D'},
  {'E', 'F', 'G', 'H'},
  {'I', 'J', 'K', 'L'}
};

const byte ROWPINS[ROWS] = {4, 5, 6};
const byte COLPINS[COLS] = {A0, A1, 2, 3};
Keypad keypad = Keypad(makeKeymap(keys), ROWPINS, COLPINS, ROWS, COLS);

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

  for (int i = 0; i < ROWS; i++) {
    pinMode(ROWPINS[i], INPUT);
  }

  for (int i = 0; i < COLS; i++) {
    pinMode(COLPINS[i], INPUT);
  }
  //pinMode(0, INPUT);
  //pinMode(1, INPUT);

}

void loop() {
  char key = keypad.getKey();

  if (key != NO_KEY) {
    Serial.println(key);
  }
}