#include  
 
Servo myservo; // create servo object to control a servo 
// a maximum of eight servo objects can be created 
 
int pos = 0; // variable to store the servo position 
 
void setup() 
{ 
  myservo.attach(9); // attaches the servo on pin 9 to the servo object 
} 
 
void loop() 
{ 
  for(pos = 0; pos < 180; pos += 1) // goes from 0 degrees to 180 degrees 
  { // in steps of 1 degree 
    myservo.write(pos); // tell servo to go to position in variable 'pos' 
    delay(15); // waits 15ms for the servo to reach the position 
  } 
  for(pos = 180; pos>=1; pos-=1) // goes from 180 degrees to 0 degrees 
  { 
    myservo.write(pos); // tell servo to go to position in variable 'pos' 
    delay(15); // waits 15ms for the servo to reach the position 
  } 
}