00001 // AccelStepper.h 00002 // 00003 /// \mainpage AccelStepper library for Arduino 00004 /// 00005 /// This is the Arduino AccelStepper 1.2 library. 00006 /// It provides an object-oriented interface for 2 or 4 pin stepper motors. 00007 /// 00008 /// The standard Arduino IDE includes the Stepper library 00009 /// (http://arduino.cc/en/Reference/Stepper) for stepper motors. It is 00010 /// perfectly adequate for simple, single motor applications. 00011 /// 00012 /// AccelStepper significantly improves on the standard Arduino Stepper library in several ways: 00013 /// \li Supports acceleration and deceleration 00014 /// \li Supports multiple simultaneous steppers, with independent concurrent stepping on each stepper 00015 /// \li API functions never delay() or block 00016 /// \li Supports 2 and 4 wire steppers 00017 /// \li Supports stepper drivers such as the Sparkfun EasyDriver (based on 3967 driver chip) 00018 /// \li Very slow speeds are supported 00019 /// \li Extensive API 00020 /// \li Subclass support 00021 /// 00022 /// The latest version of this documentation can be downloaded from 00023 /// http://www.open.com.au/mikem/arduino/AccelStepper 00024 /// 00025 /// Example Arduino programs are included to show the main modes of use. 00026 /// 00027 /// The version of the package that this documentation refers to can be downloaded 00028 /// from http://www.open.com.au/mikem/arduino/AccelStepper/AccelStepper-1.3.zip 00029 /// You can find the latest version at http://www.open.com.au/mikem/arduino/AccelStepper 00030 /// 00031 /// Tested on Arduino Diecimila and Mega with arduino-0018 on OpenSuSE 11.1 and avr-libc-1.6.1-1.15, 00032 /// cross-avr-binutils-2.19-9.1, cross-avr-gcc-4.1.3_20080612-26.5. 00033 /// 00034 /// \par Installation 00035 /// Install in the usual way: unzip the distribution zip file to the libraries 00036 /// sub-folder of your sketchbook. 00037 /// 00038 /// This software is Copyright (C) 2010 Mike McCauley. Use is subject to license 00039 /// conditions. The main licensing options available are GPL V2 or Commercial: 00040 /// 00041 /// \par Open Source Licensing GPL V2 00042 /// This is the appropriate option if you want to share the source code of your 00043 /// application with everyone you distribute it to, and you also want to give them 00044 /// the right to share who uses it. If you wish to use this software under Open 00045 /// Source Licensing, you must contribute all your source code to the open source 00046 /// community in accordance with the GPL Version 2 when your application is 00047 /// distributed. See http://www.gnu.org/copyleft/gpl.html 00048 /// 00049 /// \par Commercial Licensing 00050 /// This is the appropriate option if you are creating proprietary applications 00051 /// and you are not prepared to distribute and share the source code of your 00052 /// application. Contact info@open.com.au for details. 00053 /// 00054 /// \par Revision History 00055 /// \version 1.0 Initial release 00056 /// 00057 /// \version 1.1 Added speed() function to get the current speed. 00058 /// \version 1.2 Added runSpeedToPosition() submitted by Gunnar Arndt. 00059 /// \version 1.3 Added support for stepper drivers (ie with Step and Direction inputs) with _pins == 1 00060 /// 00061 /// 00062 /// \author Mike McCauley (mikem@open.com.au) 00063 // Copyright (C) 2009 Mike McCauley 00064 // $Id: AccelStepper.h,v 1.2 2010/10/24 07:46:18 mikem Exp mikem $ 00065 00066 #ifndef AccelStepper_h 00067 #define AccelStepper_h 00068 00069 #include <stdlib.h> 00070 #include <wiring.h> 00071 00072 // These defs cause trouble on some versions of Arduino 00073 #undef round 00074 00075 ///////////////////////////////////////////////////////////////////// 00076 /// \class AccelStepper AccelStepper.h <AccelStepper.h> 00077 /// \brief Support for stepper motors with acceleration etc. 00078 /// 00079 /// This defines a single 2 or 4 pin stepper motor, or stepper moter with fdriver chip, with optional 00080 /// acceleration, deceleration, absolute positioning commands etc. Multiple 00081 /// simultaneous steppers are supported, all moving 00082 /// at different speeds and accelerations. 00083 /// 00084 /// \par Operation 00085 /// This module operates by computing a step time in milliseconds. The step 00086 /// time is recomputed after each step and after speed and acceleration 00087 /// parameters are changed by the caller. The time of each step is recorded in 00088 /// milliseconds. The run() function steps the motor if a new step is due. 00089 /// The run() function must be called frequently until the motor is in the 00090 /// desired position, after which time run() will do nothing. 00091 /// 00092 /// \par Positioning 00093 /// Positions are specified by a signed long integer. At 00094 /// construction time, the current position of the motor is consider to be 0. Positive 00095 /// positions are clockwise from the initial position; negative positions are 00096 /// anticlockwise. The curent position can be altered for instance after 00097 /// initialization positioning. 00098 /// 00099 /// \par Caveats 00100 /// This is an open loop controller: If the motor stalls or is oversped, 00101 /// AccelStepper will not have a correct 00102 /// idea of where the motor really is (since there is no feedback of the motor's 00103 /// real position. We only know where we _think_ it is, relative to the 00104 /// initial starting point). 00105 /// 00106 /// The fastest motor speed that can be reliably supported is 1000 steps per 00107 /// second (1 step every millisecond). However any speed less than that down 00108 /// to very slow speeds (much less than one per second) are supported, 00109 /// provided the run() function is called frequently enough to step the 00110 /// motor whenever required. 00111 class AccelStepper 00112 { 00113 public: 00114 /// Constructor. You can have multiple simultaneous steppers, all moving 00115 /// at different speeds and accelerations, provided you call their run() 00116 /// functions at frequent enough intervals. Current Position is set to 0, target 00117 /// position is set to 0. MaxSpeed and Acceleration default to 1.0. 00118 /// The motor pins will be initialised to OUTPUT mode during the 00119 /// constructor by a call to enableOutputs(). 00120 /// \param[in] pins Number of pins to interface to. 1, 2 or 4 are 00121 /// supported. 1 means a stepper driver (with Step and Direction pins) 00122 /// 2 means a 2 wire stepper. 4 means a 4 wire stepper. 00123 /// Defaults to 4 pins. 00124 /// \param[in] pin1 Arduino digital pin number for motor pin 1. Defaults 00125 /// to pin 2. For a driver (pins==1), this is the Step input to the driver. Low to high transition means to step) 00126 /// \param[in] pin2 Arduino digital pin number for motor pin 2. Defaults 00127 /// to pin 3. For a driver (pins==1), this is the Direction input the driver. High means forward. 00128 /// \param[in] pin3 Arduino digital pin number for motor pin 3. Defaults 00129 /// to pin 4. 00130 /// \param[in] pin4 Arduino digital pin number for motor pin 4. Defaults 00131 /// to pin 5. 00132 AccelStepper(uint8_t pins = 4, uint8_t pin1 = 2, uint8_t pin2 = 3, uint8_t pin3 = 4, uint8_t pin4 = 5); 00133 00134 /// Set the target position. The run() function will try to move the motor 00135 /// from the current position to the target position set by the most 00136 /// recent call to this function. 00137 /// \param[in] absolute The desired absolute position. Negative is 00138 /// anticlockwise from the 0 position. 00139 void moveTo(long absolute); 00140 00141 /// Set the target position relative to the current position 00142 /// \param[in] relative The desired position relative to the current position. Negative is 00143 /// anticlockwise from the current position. 00144 void move(long relative); 00145 00146 /// Poll the motor and step it if a step is due, implementing 00147 /// accelerations and decelerations to achive the ratget position. You must call this as 00148 /// fequently as possible, but at least once per minimum step interval, 00149 /// preferably in your main loop. 00150 /// \return true if the motor is at the target position. 00151 boolean run(); 00152 00153 /// Poll the motor and step it if a step is due, implmenting a constant 00154 /// speed as set by the most recent call to setSpeed(). 00155 /// \return true if the motor was stepped. 00156 boolean runSpeed(); 00157 00158 /// Sets the maximum permitted speed. the run() function will accelerate 00159 /// up to the speed set by this function. 00160 /// \param[in] speed The desired maximum speed in steps per second. Must 00161 /// be > 0. Speeds of more than 1000 steps per second are unreliable. 00162 void setMaxSpeed(float speed); 00163 00164 /// Sets the acceleration and deceleration parameter. 00165 /// \param[in] acceleration The desired acceleration in steps per second 00166 /// per second. Must be > 0. 00167 void setAcceleration(float acceleration); 00168 00169 /// Sets the desired constant speed for use with runSpeed(). 00170 /// \param[in] speed The desired constant speed in steps per 00171 /// second. Positive is clockwise. Speeds of more than 1000 steps per 00172 /// second are unreliable. Very slow speeds may be set (eg 0.00027777 for 00173 /// once per hour, approximately. Speed accuracy depends on the Arduino 00174 /// crystal. Jitter depends on how frequently you call the runSpeed() function. 00175 void setSpeed(float speed); 00176 00177 /// The most recently set speed 00178 /// \return the most recent speed in steps per second 00179 float speed(); 00180 00181 /// The distance from the current position to the target position. 00182 /// \return the distance from the current position to the target position 00183 /// in steps. Positive is clockwise from the current position. 00184 long distanceToGo(); 00185 00186 /// The most recently set target position. 00187 /// \return the target position 00188 /// in steps. Positive is clockwise from the 0 position. 00189 long targetPosition(); 00190 00191 00192 /// The currently motor position. 00193 /// \return the current motor position 00194 /// in steps. Positive is clockwise from the 0 position. 00195 long currentPosition(); 00196 00197 /// Resets the current position of the motor, so that wherever the mottor 00198 /// happens to be right now is considered to be the new position. Useful 00199 /// for setting a zero position on a stepper after an initial hardware 00200 /// positioning move. 00201 /// \param[in] position The position in steps of wherever the motor 00202 /// happens to be right now. 00203 void setCurrentPosition(long position); 00204 00205 /// Moves the motor to the target position and blocks until it is at 00206 /// position. Dont use this in event loops, since it blocks. 00207 void runToPosition(); 00208 00209 /// Runs at the currently selected speed until the target position is reached 00210 /// Does not implement accelerations. 00211 boolean runSpeedToPosition(); 00212 00213 /// Moves the motor to the new target position and blocks until it is at 00214 /// position. Dont use this in event loops, since it blocks. 00215 /// \param[in] position The new target position. 00216 void runToNewPosition(long position); 00217 00218 /// Disable motor pin outputs by setting them all LOW 00219 /// Depending on the design of your electronics this may turn off 00220 /// the power to the motor coils, saving power. 00221 /// This is useful to support Arduino low power modes: disable the outputs 00222 /// during sleep and then reenable with enableOutputs() before stepping 00223 /// again. 00224 void disableOutputs(); 00225 00226 /// Enable motor pin outputs by setting the motor pins to OUTPUT 00227 /// mode. Called automatically by the constructor. 00228 void enableOutputs(); 00229 00230 protected: 00231 00232 /// Forces the library to compute a new instantaneous speed and set that as 00233 /// the current speed. Calls 00234 /// desiredSpeed(), which can be overridden by subclasses. It is called by 00235 /// the library: 00236 /// \li after each step 00237 /// \li after change to maxSpeed through setMaxSpeed() 00238 /// \li after change to acceleration through setAcceleration() 00239 /// \li after change to target position (relative or absolute) through 00240 /// move() or moveTo() 00241 void computeNewSpeed(); 00242 00243 /// Called to execute a step. Only called when a new step is 00244 /// required. Subclasses may override to implement new stepping 00245 /// interfaces. The default calls step1(), step2() or step4() depending on the 00246 /// number of pins defined for the stepper. 00247 /// \param[in] step The current step phase number (0 to 3) 00248 virtual void step(uint8_t step); 00249 00250 00251 /// Called to execute a step on a stepper drover (ie where pins == 1). Only called when a new step is 00252 /// required. Subclasses may override to implement new stepping 00253 /// interfaces. The default sets or clears the outputs of Step pin1 to step, 00254 /// and sets the output of _pin2 to the desired direction. The Step pin (_pin1) is pulsed for 1 microsecond 00255 /// which is the minimum STEP pulse width for the 3967 driver. 00256 /// \param[in] step The current step phase number (0 to 3) 00257 virtual void step1(uint8_t step); 00258 00259 /// Called to execute a step on a 2 pin motor. Only called when a new step is 00260 /// required. Subclasses may override to implement new stepping 00261 /// interfaces. The default sets or clears the outputs of pin1 and pin2 00262 /// \param[in] step The current step phase number (0 to 3) 00263 virtual void step2(uint8_t step); 00264 00265 /// Called to execute a step on a 4 pin motor. Only called when a new step is 00266 /// required. Subclasses may override to implement new stepping 00267 /// interfaces. The default sets or clears the outputs of pin1, pin2, 00268 /// pin3, pin4. 00269 /// \param[in] step The current step phase number (0 to 3) 00270 virtual void step4(uint8_t step); 00271 00272 /// Compute and return the desired speed. The default algorithm uses 00273 /// maxSpeed, acceleration and the current speed to set a new speed to 00274 /// move the motor from teh current position to the target 00275 /// position. Subclasses may override this to provide an alternate 00276 /// algorithm (but do not block). Called by computeNewSpeed whenever a new speed neds to be 00277 /// computed. 00278 virtual float desiredSpeed(); 00279 00280 private: 00281 /// Number of pins on the stepper motor. Permits 2 or 4. 2 pins is a 00282 /// bipolar, and 4 pins is a unipolar. 00283 uint8_t _pins; // 2 or 4 00284 00285 /// Arduino pin number for the 2 or 4 pins required to interface to the 00286 /// stepper motor. 00287 uint8_t _pin1, _pin2, _pin3, _pin4; 00288 00289 /// The current absolution position in steps. 00290 long _currentPos; // Steps 00291 00292 /// The target position in steps. The AccelStepper library will move the 00293 /// motor from teh _currentPos to the _targetPos, taking into account the 00294 /// max speed, acceleration and deceleration 00295 long _targetPos; // Steps 00296 00297 /// The current motos speed in steps per second 00298 /// Positive is clockwise 00299 float _speed; // Steps per second 00300 00301 /// The maximum permitted speed in steps per second. Must be > 0. 00302 float _maxSpeed; 00303 00304 /// The acceleration to use to accelerate or decelerate the motor in steps 00305 /// per second per second. Must be > 0 00306 float _acceleration; 00307 00308 /// The current interval between steps in milliseconds. 00309 unsigned long _stepInterval; 00310 00311 /// The last step time in milliseconds 00312 unsigned long _lastStepTime; 00313 }; 00314 00315 #endif
1.5.6