#include <Servo.h> 
// Declare the Servo pin 
int servoPin = 9; 
Servo Servo1; 
void setup() { 
   // We need to attach the servo to the used pin number 
   Servo1.attach(servoPin); 
}
void loop(){ 
   // Make servo go to 180 degrees 
   Servo1.write(180); 
   delay(1000); 

   // Make servo go to 0 degrees 
   Servo1.write(-180); 
   delay(1000); 
}