/*
    Digital Ports as Objects
    2023-05-19
*/
class Output {
  protected:
    const uint8_t pin;    // the GPIO used for output
    const int8_t active;  // HIGH active (default), or LOW active
  public:
    Output (uint8_t pin, int8_t active = HIGH) : pin(pin), active(active) {}
    void begin() {        // initialize pin in setup()
      pinMode(pin, OUTPUT);
      this->off();        // optional
    }
    void on() {           // switch pin on
      digitalWrite(pin, active);
    }
    void off() {          // switch pin off
      digitalWrite(pin, active == HIGH ? LOW : HIGH);
    }
};

Output led(13);           // active HIGH (default)
Output relay(7, LOW);     // active LOW (inverse)

void setup() {
  led.begin();
  relay.begin();
}

void loop() {
  led.on();
  relay.on();
  delay(500);
  led.off();
  relay.off();
  delay(500);
}