#include <Keypad.h>
#include <LiquidCrystal_I2C.h>

const int ROW_NUM    = 4; // four rows
const int COLUMN_NUM = 4; // four columns

char keys[ROW_NUM][COLUMN_NUM] = {
  {'1','2','3', 'A'},
  {'4','5','6', 'B'},
  {'7','8','9', 'C'},
  {'*','0','#', 'D'}
};

byte pin_rows[ROW_NUM] = {8, 7, 6, 5};      // connect to the row pinouts of the keypad
byte pin_column[COLUMN_NUM] = {4, 3, 2, 1}; // connect to the column pinouts of the keypad

Keypad keypad = Keypad(makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COLUMN_NUM );

LiquidCrystal_I2C lcd(0x27, 16, 2); // I2C address 0x27, 16 column and 2 rows

int cursorColumn = 0;

void setup(){
  lcd.init(); // initialize the lcd
  lcd.backlight();
  Serial.begin(9600);
}

void loop(){
  char key = keypad.getKey();
  if (key) {
    Serial.print(key);
    lcd.setCursor(cursorColumn, 0); // move cursor to   (cursorColumn, 0)
    lcd.print(key);                 // print key at (cursorColumn, 0)
    cursorColumn++;                 // move cursor to next position
    if(cursorColumn == 16) {        // if reaching limit, clear LCD
      lcd.clear();
      cursorColumn = 0;
    }
  }
}