초음파센서로 서보모터 움직이기>> 
#include <Servo.h>
 
Servo servo; 
 
#define trig 7  
#define echo 6  
int angle =0;
int sw = 10; 
int led = 6;
 
int state = LOW;    
int reading;         
int previous = LOW;   
 
long time = 0;        
long debounce = 100;  
 
void setup() { 
  servo.attach(2);
  Serial.begin(9600);
  pinMode(trig, OUTPUT);  
  pinMode(echo, INPUT); 
  pinMode(sw, INPUT_PULLUP); 
  pinMode(led, OUTPUT); 
} 
 
void loop()
{
  long duration,distance;
  digitalWrite(trig, LOW);  
  digitalWrite(echo, LOW);
  delayMicroseconds(2);  
  digitalWrite(trig, HIGH);  
  delayMicroseconds(10); 
  digitalWrite(trig, LOW); 
 
  duration = pulseIn(echo, HIGH);
  distance = ((float)(340*duration)/10000)/2;
 
  Serial.print("거리:");
  Serial.print(distance);
  Serial.println("cm");
 
 if (distance<10) {
  angle=70;
  Serial.println("문이 열렸습니다.");
  delay(500);
}
else{
  angle=180;
  delay(500);
  }
  servo.write(angle);
 
  reading = digitalRead(sw);  
 
 
  if (reading == HIGH && previous == LOW && millis() - time > debounce) {
    if (state == HIGH)   
      state = LOW;
    else           .
      state = HIGH;
 
    time = millis();
  }
 
  digitalWrite(led, state);
 
  previous = reading;
}
 
택트스위치로 led켜기>>
int sw = 10;      
int led = 6;     
 
int state = LOW;    
int reading;      
int previous = LOW;   
 
long time = 0;     
long debounce = 100;  
 
void setup()
{
  pinMode(sw, INPUT_PULLUP);
  pinMode(led, OUTPUT);    
}
 
void loop()
{
  reading = digitalRead(sw);  
 
 
  if (reading == HIGH && previous == LOW && millis() - time > debounce) {
    if (state == HIGH)   
      state = LOW;
    else                  
      state = HIGH;
 
    time = millis();
  }
 
  digitalWrite(led, state);
 
  previous = reading;
}