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/*
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  Stepper.h - - Stepper library for Wiring/Arduino - Version 0.4
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  Original library     (0.1) by Tom Igoe.
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  Two-wire modifications   (0.2) by Sebastian Gassner
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  Combination version   (0.3) by Tom Igoe and David Mellis
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  Bug fix for four-wire   (0.4) by Tom Igoe, bug fix from Noah Shibley
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  Drives a unipolar or bipolar stepper motor using  2 wires or 4 wires
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  When wiring multiple stepper motors to a microcontroller,
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  you quickly run out of output pins, with each motor requiring 4 connections. 
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  By making use of the fact that at any time two of the four motor
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  coils are the inverse  of the other two, the number of
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  control connections can be reduced from 4 to 2. 
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  A slightly modified circuit around a Darlington transistor array or an L293 H-bridge
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  connects to only 2 microcontroler pins, inverts the signals received,
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  and delivers the 4 (2 plus 2 inverted ones) output signals required
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  for driving a stepper motor.
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  The sequence of control signals for 4 control wires is as follows:
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  Step C0 C1 C2 C3
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     1  1  0  1  0
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     2  0  1  1  0
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     3  0  1  0  1
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     4  1  0  0  1
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  The sequence of controls signals for 2 control wires is as follows
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  (columns C1 and C2 from above):
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  Step C0 C1
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     1  0  1
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     2  1  1
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     3  1  0
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     4  0  0
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  The circuits can be found at 
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  http://www.arduino.cc/en/Tutorial/Stepper
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*/
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// ensure this library description is only included once
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#ifndef Stepper_h
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#define Stepper_h
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// library interface description
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class Stepper {
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  public:
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    // constructors:
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    Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2);
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    Stepper(int number_of_steps, int motor_pin_1, int motor_pin_2, int motor_pin_3, int motor_pin_4);
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    // speed setter method:
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    void setSpeed(long whatSpeed);
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    // mover method:
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    void step(int number_of_steps);
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    int version(void);
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  private:
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    void stepMotor(int this_step);
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    int direction;        // Direction of rotation
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    int speed;          // Speed in RPMs
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    unsigned long step_delay;    // delay between steps, in ms, based on speed
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    int number_of_steps;      // total number of steps this motor can take
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    int pin_count;        // whether you're driving the motor with 2 or 4 pins
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    int step_number;        // which step the motor is on
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    // motor pin numbers:
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    int motor_pin_1;
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    int motor_pin_2;
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    int motor_pin_3;
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    int motor_pin_4;
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    long last_step_time;      // time stamp in ms of when the last step was taken
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};
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#endif
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