#include <Keypad.h>
int led1 = 13;
int led2 = 11;

const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char keys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};

uint8_t colPins[COLS] = { 5, 4, 3, 2 }; // Pins connected to C1, C2, C3, C4
uint8_t rowPins[ROWS] = { 9, 8, 7, 6 }; // Pins connected to R1, R2, R3, R4

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

void setup() {
  Serial.begin(9600);
  pinMode(led1, OUTPUT);
  pinMode(led2, OUTPUT);
}

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

  if (key != NO_KEY) {
    Serial.println(key);
    if (key == 'A'){
      digitalWrite(led1, HIGH);
      Serial.println("หลอด LED สีแดง ติด");
    }
    else if (key == 'B'){
      digitalWrite(led1, LOW);
      Serial.println("หลอด LED สีแดง ดับ");
    }
    else if (key == 'C'){
      digitalWrite(led2, HIGH);
      Serial.println("หลอด LED สีเหลือง ติด");
    }
    else if (key == 'D'){
      digitalWrite(led2, LOW);
      Serial.println("หลอด LED สีเหลือง ดับ");
    }
  }
}