Arduino Uno + Keypad 4x4 + LCD I2C

Kebutuhan hardware:

• Arduino Uno + USB kabel
• Keypad 4x4 Matrix
• LCD 16x2 I2C
• Kabel Jumper Dupont

Diagram

Langkah - langkah:

- Pastikan sudah menginstall library Keypad dan LCD I2C

- Upload code berikut menggunakan Arduino IDE

#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] = {9, 8, 7, 6};      // Pin baris keypad
byte pin_column[COLUMN_NUM] = {5, 4, 3, 2}; // Pin kolom keypad

Keypad keypad = Keypad(makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COLUMN_NUM );
LiquidCrystal_I2C lcd(0x27, 16, 2); // alamat I2C 0x27, 16 kolom and 2 baris LCD

int cursorColumn = 0;

void setup(){
  lcd.init(); // inisialisasi LCD
  lcd.backlight();
}

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

  if (key) {
    lcd.setCursor(cursorColumn, 0); // posisikan kursor ke (cursorColumn, 0)
    lcd.print(key);                 // print key pada (cursorColumn, 0)

    cursorColumn++;                 // pindah kursor ke posisi berikutnya
    if(cursorColumn == 16) {        // jika kolom sampai posisi akhir, clear LCD
      lcd.clear();
      cursorColumn = 0;
    }
  }
}