Reverse turning of Stepper motor

Question

I have a stepper motor connected to my Arduino like this using the ULN2003A Darlington Array:

(Ignore the potentiometer)

And I have programmed it with the following code:

#include <Stepper.h>

int in1Pin = 22;
int in2Pin = 23;
int in3Pin = 24;
int in4Pin = 25;

Stepper motor(512, in1Pin, in2Pin, in3Pin, in4Pin);

void setup()
{
    pinMode(in1Pin, OUTPUT);
    pinMode(in2Pin, OUTPUT);
    pinMode(in3Pin, OUTPUT);
    pinMode(in4Pin, OUTPUT);

    motor.setSpeed(25);
}

void loop()
{
    int steps = 360;

    motor.step(steps);
    delay(500);
}

At the moment the motor rotates clockwise, how could I have it so it rotates in the opposite direction?

My code was copied and edited from here.

---

The problem was that I had the two middle wires the wrong way round as said here: http://forum.arduino.cc/index.php?PHPSESSID=kvi8dt2b5en5hhk02dlmjrotl5&topic=143276.msg‌​

Answer 1

The answer is simple. Just pass a negative number of steps as an argument to motor.step();.

Another note: You forgot a semicolon on your second to last line. IIRC this doesn't matter in C, but it's just bad practice to do this. If you add a line of code below that, then it won't work.

Example code:

#include <Stepper.h>

int in1Pin = 22;
int in2Pin = 23;
int in3Pin = 24;
int in4Pin = 25;

Stepper motor(512, in1Pin, in2Pin, in3Pin, in4Pin);

void setup()
{
    pinMode(in1Pin, OUTPUT);
    pinMode(in2Pin, OUTPUT);
    pinMode(in3Pin, OUTPUT);
    pinMode(in4Pin, OUTPUT);

    motor.setSpeed(25);
}

void loop()
{
    int steps = 360;
    motor.step(steps);
    delay(100);

    steps = -360;
    motor.step(steps);
    delay(500); //Semicolon added
}