#include <Wire.h>
#include <Keypad.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define LEBAR_LAYAR 128
#define TINGGI_LAYAR 64

Adafruit_SSD1306 oled(LEBAR_LAYAR, TINGGI_LAYAR, &Wire, -1);
const byte BARIS=4;
const byte KOLOM=4;

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

byte rowPins[BARIS]={14,12,19,18};
byte colPins[KOLOM]={5,4,2,15};

Keypad customKeypad = Keypad(makeKeymap(hexaKeys),rowPins,colPins,BARIS,KOLOM);

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

  // initialize OLED display with I2C address 0x3C
  if (!oled.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("failed to start SSD1306 OLED"));
    while (1);
  }

  delay(2000);         
  oled.clearDisplay(); // clear display

  oled.setTextSize(2);         // Atur ukuran text
  oled.setTextColor(WHITE);    // Atur warna text
  oled.setCursor(0, 10);       // Atur posisi text pada display
  oled.println("Keypad ESP32"); // Text yang dicetak
  delay(2000);
  oled.display(); 
  oled.clearDisplay();
}

void loop() {
  char customKey = customKeypad.getKey();
    if (customKey){

    oled.setTextSize(2);
    oled.setTextColor(WHITE); 
    oled.setCursor(0,10);
    oled.print("Press: ");
    oled.print(customKey);
    oled.display();
    oled.clearDisplay();
    delay(100);

  }
}