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      1 /*
      2  * Author: Jon Trulson <jtrulson (at) ics.com>
      3  * Copyright (c) 2015 Intel Corporation.
      4  *
      5  * Permission is hereby granted, free of charge, to any person obtaining
      6  * a copy of this software and associated documentation files (the
      7  * "Software"), to deal in the Software without restriction, including
      8  * without limitation the rights to use, copy, modify, merge, publish,
      9  * distribute, sublicense, and/or sell copies of the Software, and to
     10  * permit persons to whom the Software is furnished to do so, subject to
     11  * the following conditions:
     12  *
     13  * The above copyright notice and this permission notice shall be
     14  * included in all copies or substantial portions of the Software.
     15  *
     16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     19  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
     20  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     21  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     22  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
     23  */
     24 #pragma once
     25 
     26 #include <stdint.h>
     27 #include <sys/time.h>
     28 
     29 #include <mraa/gpio.h>
     30 #include <mraa/pwm.h>
     31 
     32 // in milliseconds
     33 #define L298_DEFAULT_PWM_PERIOD 4
     34 
     35 namespace upm {
     36   /**
     37    * @brief L298 Dual H-Bridge Motor Driver library
     38    * @defgroup l298 libupm-l298
     39    * @ingroup seeed sparkfun gpio pwm motor
     40    */
     41 
     42   /**
     43    * @library l298
     44    * @sensor l298
     45    * @comname L298 Dual H-Bridge Motor Driver
     46    * @type motor
     47    * @man seeed sparkfun
     48    * @web https://www.sparkfun.com/products/9670
     49    * @con gpio pwm
     50    *
     51    * @brief API for the L298 Dual H-Bridge Motor Driver
     52    *
     53    * It was developed using the RobotBase Dual H-Bridge module.
     54    *
     55    * This module can support 2 DC motors, or one 2-phase stepper motor.
     56    * It requires 3 pins per DC motor (or H-bridge), or 4 pins for
     57    * the stepper motor (uses both H-bridges).
     58    *
     59    * @image html l298.jpg
     60    * <br><em>L298 Dual H-Bridge Motor Driver image provided by SparkFun* under
     61    * <a href=https://creativecommons.org/licenses/by-nc-sa/3.0/>
     62    * CC BY-NC-SA-3.0</a>.</em>
     63    *
     64    * Example driving a DC motor
     65    * @snippet l298.cxx Interesting
     66    * Example driving a stepper motor
     67    * @snippet l298-stepper.cxx Interesting
     68    */
     69   class L298 {
     70   public:
     71 
     72     /**
     73      * Enum to specify the direction of a motor
     74      */
     75     typedef enum {
     76       DIR_NONE = 0x00,
     77       DIR_CW   = 0x01,
     78       DIR_CCW  = 0x02
     79     } L298_DIRECTION_T;
     80 
     81     /**
     82      * L298 constructor for DC motor(s) connected.
     83      *
     84      * @param pwm Digital pin to use for a DC motor - must be PWM-capable
     85      * @param dir1 Digital pin to use for motor direction pin 1
     86      * @param dir2 Digital pin to use for motor direction pin 2
     87      */
     88     L298(int pwm, int dir1, int dir2);
     89 
     90     /**
     91      * L298 constructor for a 4-wire stepper motor
     92      *
     93      * @param stepsPerRev Number of steps per full revolution
     94      * @param en Enables the pin
     95      * @param i1 Digital pin to use for stepper input 1
     96      * @param i2 Digital pin to use for stepper input 2
     97      * @param i3 Digital pin to use for stepper input 3
     98      * @param i4 Digital pin to use for stepper input 4
     99      */
    100     L298(int stepsPerRev, int en, int i1, int i2, int i3, int i4);
    101 
    102     /**
    103      * L298 destructor
    104      */
    105     ~L298();
    106 
    107     /**
    108      * Returns the number of milliseconds elapsed since initClock()
    109      * was last called.
    110      *
    111      * @return Elapsed milliseconds
    112      */
    113     uint32_t getMillis();
    114 
    115     /**
    116      * Resets the clock
    117      *
    118      */
    119     void initClock();
    120 
    121     /**
    122      * Sets the period in milliseconds
    123      *
    124      * @param ms Period in milliseconds
    125      */
    126     void setPeriodMS(int ms);
    127 
    128     /**
    129      * Enables the PWM output for a motor
    130      *
    131      * @param enable Enables the PWM output if true, disables if false
    132      */
    133     void enable(bool enable);
    134 
    135     /**
    136      * Sets the speed of a DC or stepper motor. For a DC motor, values
    137      * can range from 0 (off) to 100 (full speed). For a stepper
    138      * motor, specify the desired RPM.
    139      *
    140      * @param speed Speed to set the motor to
    141      */
    142     void setSpeed(int speed);
    143 
    144     /**
    145      * Sets the direction of the motor, clockwise or counterclockwise
    146      *
    147      * @param dir Direction to set the motor to
    148      */
    149     void setDirection(L298_DIRECTION_T dir);
    150 
    151     /**
    152      * Steps the stepper motor a specified number of steps
    153      *
    154      * @param steps Number of steps to move the stepper motor
    155      */
    156     void stepperSteps(unsigned int steps);
    157 
    158   private:
    159     // DC motor mode enabled
    160     bool m_motor;
    161     // stepper mode enabled
    162     bool m_stepper;
    163 
    164     struct timeval m_startTime;
    165 
    166     // DC motor
    167     mraa_pwm_context m_pwm;
    168     mraa_gpio_context m_dir1;
    169     mraa_gpio_context m_dir2;
    170 
    171     // stepper (4-wire)
    172     mraa_gpio_context m_stepEnable;
    173     mraa_gpio_context m_stepI1;
    174     mraa_gpio_context m_stepI2;
    175     mraa_gpio_context m_stepI3;
    176     mraa_gpio_context m_stepI4;
    177 
    178     // steps per revolution
    179     int m_stepsPerRev;
    180     int m_currentStep;
    181     uint32_t m_stepDelay;
    182 
    183     /**
    184      * Steps the motor one tick
    185      *
    186      */
    187     void stepperStep();
    188 
    189     // step direction: - 1 = forward, -1 = backward
    190     int m_stepDirection;
    191   };
    192 }
    193 
    194 
    195