Switch toggle control source(Button, LED)

** 버튼 토글

const int LED = 3;
const int Btn = 7;

int ledState = 0;
int buttonState = 0;
int p_buttonState = 0;

void setup()
{
  Serial.begin(9600);
  pinMode(LED, OUTPUT);
  pinMode(Btn, INPUT);
}

void loop()
{
  int reading = digitalRead(Btn);
  if (reading != p_buttonState)
  {
    buttonState = reading;
    if(buttonState == HIGH)
    {
      ledState = !ledState;
    }
  }
  
  digitalWrite(LED, ledState);
  p_buttonState = reading;
}

const int LED = 3;
const int Btn = 7;

int flag1 = 0;
int flag2 = 0;
int state = 0;

void setup()
{
  pinMode(LED, OUTPUT);
  pinMode(Btn, INPUT);
}

void loop()
{
  flag1 = digitalRead(Btn);
  if((flag1 == HIGH) && (flag2 == LOW))
  {
    state = !state;
    delay(10);
  }
  flag2 = flag1;
  
  if (state == 1)
  {
    digitalWrite(LED, HIGH);
  }
  else
  {
    digitalWrite(LED, LOW);
  }
}

---

** millis() 함수를 활용한 LED 점멸

const int LED = 3;
const int Btn = 7;

int ledState = 0;
unsigned long interval = 1000;
unsigned long previousMillis = 0;

void setup()
{
  Serial.begin(9600);
  pinMode(LED, OUTPUT);
  pinMode(Btn, INPUT);
}

void loop()
{
  unsigned long currentMillis = millis();
  if(currentMillis - previousMillis > interval)
  {
    previousMillis = currentMillis;
    
    if(ledState == LOW)
    {
      ledState = HIGH;      
    }
    else
    {
      ledState = LOW;
    }
    digitalWrite(LED, ledState);
  }
  
}

---

** 버튼 누른 시간에 따른 동작 소스 코드 (Button: pull-down)

/* LED */
const int LED = 3;

/* Button */
const int Btn = 7;
const int button_interval = 5000; // 5Sec.
long button_pressed_millis;

/* Time */
long current_millis;
bool isActive = false;
const int check_interval = 100;

void setup()
{
  button_pressed_millis = 0;
  
  pinMode(LED, OUTPUT);
  pinMode(Btn, INPUT);
}

void loop()
{
  current_millis = millis(); // record current time
  
  if(digitalRead(Btn) == HIGH &&
     current_millis - button_pressed_millis > button_interval)
  {
    button_pressed_millis = current_millis;
    isActive = (isActive) ? false : true;
  }
  
  if(isActive)
  {
    digitalWrite(LED, HIGH);
  }
  else
  {
    digitalWrite(LED,LOW);
  }
  delay(check_interval);
}