#include <Stepper.h>

/*  A 4 wire bipolar, or 5 or 6 wire unipolar stepper motor drives a 1mm pitch 
 threaded rod that rotates a camera mount arm, approximating the 
 siderial rate (15.0401 deg/hour), for extended exposures of the night sky.
 
 Forward, Reverse and Stop are controlled by a 3 position switch.
 Reverse returns the camera arm to it's starting point at 60RPM until
 contacting a kill switch: The Forward function overrides the kill switch.
 
 If intending to use a unipolar motor, uncomment #define motorPin1 8 through 11,
 and comment the lines #define motorPin1 4 through 7.
 
 It is also possible to drive a unipolar motor without the centre tap. Identify
 the coils and connect as a bipolar.
 
 Note: it may be necessary to change the motorSteps line to suit your stepper;
 e.g., if your stepper has 200 steps, set the line to #define motorSteps 200
 
 An LED flashes while reversing and is steady while the drive is stopped.
 
 Selecting Serial Monitor will print out the time that the program has run.
 
 */

// global

int pinval2; // pin2 value HIGH or LOW
int pinval3; // pin3 value HIGH or LOW
int Pin2 = 2; // Pin2 INPUT, HIGH, pull-up resistors
int Pin3 = 3; // Pin3 INPUT, pull-up resistors
int ledPin = 13;

#define motorSteps 400
#define motorPin1 4
#define motorPin2 5
#define motorPin3 6
#define motorPin4 7

/* Uncomment to use unipolar motor
 #define motorPin1 8
 #define motorPin2 9
 #define motorPin3 10
 #define motorPin4 11
 */

// initialize Stepper library:
Stepper Stepper1(motorSteps, motorPin1,motorPin2,motorPin3,motorPin4);

void setup(){
  pinMode(Pin2, INPUT); // define as input
  pinMode(Pin3, INPUT);
  digitalWrite(Pin2, HIGH); // activate pull-up resistors
  digitalWrite(Pin3, HIGH);
  pinMode(ledPin, OUTPUT);
}
void loop(){
  { // forward
    digitalWrite(ledPin, LOW); // turn LED off
    pinval2 = digitalRead(Pin2); // read Pin value
    pinval3 = digitalRead(Pin3);
    if (pinval2 == HIGH && pinval3 == HIGH) // check Pin values
    {
      Stepper1.setSpeed(1.0);
      Stepper1.step(1);
    }   
    else
    { // stop
      pinval2 = digitalRead(Pin2);
      pinval3 = digitalRead(Pin3); 
      if (pinval2 == HIGH && pinval3 == LOW)
      {
        digitalWrite(ledPin, HIGH); // turn LED on
        Stepper1.setSpeed(0); 
        Stepper1.step(0);
      }
      else
      { // reverse
        pinval2 = digitalRead(Pin2);
        pinval3 = digitalRead(Pin3);
        if (pinval2 == LOW && pinval3 == LOW)
        {
          digitalWrite(ledPin, HIGH);
          Stepper1.setSpeed(60);
          Stepper1.step(-1);
        }
      }
    }
  }
}