#include <Stepper.h>
 
const int stepsPerRotate = 200;//Number of Steps = 360 / Step Angle = 360 / 7.5 = 48
Stepper myStepper(stepsPerRotate, 4, 6, 5, 7);
 
void setup(){
  
}
 
void loop(){
  myStepper.setSpeed(15);
  myStepper.step(200);
  delay(500);
  myStepper.step(-200);
  myStepper.setSpeed(30);
  myStepper.step(200);
  delay(500);
  myStepper.setSpeed(50);
  myStepper.step(-200);
  delay(500);
  myStepper.setSpeed(80);
  myStepper.step(200);
  delay(500);
}