/*
  Stepper.h - - Stepper library for Wiring/Arduino - Version 0.5
  
  Original library     (0.1) by Tom Igoe.
  Two-wire modifications   (0.2) by Sebastian Gassner
  Combination version   (0.3) by Tom Igoe and David Mellis
  Bug fix for four-wire   (0.4) by Tom Igoe, bug fix from Noah Shibley
  High-speed stepping mod and timer rollover fix   (0.5) by Eugene Kozlenko

  Drives a unipolar or bipolar stepper motor using  2 wires or 4 wires

  When wiring multiple stepper motors to a microcontroller,
  you quickly run out of output pins, with each motor requiring 4 connections. 

  By making use of the fact that at any time two of the four motor
  coils are the inverse  of the other two, the number of
  control connections can be reduced from 4 to 2. 

  A slightly modified circuit around a Darlington transistor array or an L293 H-bridge
  connects to only 2 microcontroler pins, inverts the signals received,
  and delivers the 4 (2 plus 2 inverted ones) output signals required
  for driving a stepper motor.  Similarly the Arduino motor shields 2 direction pins
  may be used.

  The sequence of control signals for 4 control wires is as follows:

  Step C0 C1 C2 C3
     1  1  0  1  0
     2  0  1  1  0
     3  0  1  0  1
     4  1  0  0  1

  The sequence of controls signals for 2 control wires is as follows
  (columns C1 and C2 from above):

  Step C0 C1
     1  0  1
     2  1  1
     3  1  0
     4  0  0

  The circuits can be found at 
  http://www.arduino.cc/en/Tutorial/Stepper

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

// ensure this library description is only included once
#ifndef Stepper_h
#define Stepper_h

// library interface description
class Stepper {
  public:
    // constructors:
    Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2);
    Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2, int motor_pin_3, int motor_pin_4);

    // speed setter method:
    void setSpeed(long whatSpeed);

    // mover method:
    void step(int number_of_steps);

    int version(void);

  private:
    void stepMotor(int this_step);
    
    int direction;        // Direction of rotation
    int speed;          // Speed in RPMs
    unsigned long step_delay;    // delay between steps, in us, based on speed
    int number_of_steps;      // total number of steps this motor can take
    int pin_count;        // whether you're driving the motor with 2 or 4 pins
    int step_number;        // which step the motor is on
    
    // motor pin numbers:
    int motor_pin_1;
    int motor_pin_2;
    int motor_pin_3;
    int motor_pin_4;
    
    unsigned long last_step_time;      // time stamp in us of when the last step was taken
};

#endif