Bài 1: Làm Quen Với Arduino C++ Và Đèn LED

// Khai bao cac chan noi den LED

const int LED_RED    = 9;  // LED Do noi chan D9

const int LED_YELLOW = 10; // LED Vang noi chan D10

const int LED_GREEN  = 11; // LED Xanh noi chan D11


void setup() {
  // Cau hinh cac chan GPIO la ngo ra (OUTPUT)

  pinMode(LED_RED, OUTPUT);
  pinMode(LED_YELLOW, OUTPUT);
  pinMode(LED_GREEN, OUTPUT);

  // Khoi tao trang thai tat tat ca cac den

  digitalWrite(LED_RED, LOW);
  digitalWrite(LED_YELLOW, LOW);
  digitalWrite(LED_GREEN, LOW);
}

void loop() {
  // 1. Bat LED Do, tat cac LED con lai trong 1000ms (1 giay)

  digitalWrite(LED_RED, HIGH);
  digitalWrite(LED_YELLOW, LOW);
  digitalWrite(LED_GREEN, LOW);
  delay(1000);

  // 2. Bat LED Vang trong 500ms

  digitalWrite(LED_RED, LOW);
  digitalWrite(LED_YELLOW, HIGH);
  digitalWrite(LED_GREEN, LOW);
  delay(500);

  // 3. Bat LED Xanh trong 1000ms

  digitalWrite(LED_RED, LOW);
  digitalWrite(LED_YELLOW, LOW);
  digitalWrite(LED_GREEN, HIGH);
  delay(1000);
}