rotajig.ino

#include <Servo.h>

Servo myservo;
int pos = 0;

#define DELAY_TIME_MS 30

void setup() {
  myservo.attach(9);
}

void loop() {
  
  myservo.attach(9);
  for (pos = 1; pos <= 179; pos += 1) {  // goes from 1 degrees to 179 degrees (don't go all the way from 0 to 180 on cheap servos)
    // in steps of 1 degree

    myservo.write(pos);  // tell servo to go to position in variable 'pos'
    delay(DELAY_TIME_MS);
  }
  myservo.detach(); //detatch to prevent vibration on cheap servos during delay

  delay(DELAY_TIME_MS * 180);

  myservo.attach(9);
  for (pos = 179; pos >= 1; pos -= 1) {  // goes from 179 degrees to 1 degrees (don't go all the way from 0 to 180 on cheap servos)
    myservo.write(pos);                  // tell servo to go to position in variable 'pos'
    delay(DELAY_TIME_MS);
  }
  myservo.detach(); //detatch to prevent vibration on cheap servos during delay

  delay(DELAY_TIME_MS * 180);
}