#include <AccelStepper.h>

#define pul 16
#define dir 17

// Define some steppers and the pins the will use
AccelStepper stepper1(1,pul,dir); // Defaults to AccelStepper::FULL4WIRE (4 pins) on 2, 3, 4, 5

void setup()
{  
    stepper1.setMaxSpeed(200.0);
    stepper1.setAcceleration(100.0);
    stepper1.moveTo(200);
}

void loop()
{
    // Change direction at the limits
    if (stepper1.distanceToGo() == 0)
	stepper1.moveTo(-stepper1.currentPosition());
    stepper1.run();
}