peripheral/libupm/src/grovemd/grovemd.h

/*
 * Author: Jon Trulson <jtrulson@ics.com>
 * Copyright (c) 2014 Intel Corporation.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#pragma once

#include <stdint.h>
#include <sys/time.h>
#include <string>
#include <mraa/types.hpp>
#include <mraa/i2c.hpp>

#define GROVEMD_I2C_BUS 0
#define GROVEMD_DEFAULT_I2C_ADDR 0x0f

namespace upm {
  /**
   * @brief Grove I2C Motor Driver library
   * @defgroup grovemd libupm-grovemd
   * @ingroup seeed i2c motor robok
   */

  /**
   * @library grovemd
   * @sensor grovemd
   * @comname Grove I2C Motor Driver
   * @type motor
   * @man seeed
   * @con i2c
   * @kit robok
   *
   * @brief API for the Grove I2C Motor Driver 
   *
   * This class implements support for the Grove I2C Motor Driver.
   * This device can support a single 4-wire stepper motor, or two
   * 2-wire DC motors. The device contains an Atmel* ATmega8L
   * microcontroller that manages an L298N H-bridge driver chip.
   *
   * This device supports an I2C bus speed of 100Khz only.
   *
   * The module does not provide any telemetry or status - it only
   * accepts I2C commands for its various operations.
   *
   * This module was tested with version 1.3 of the Grove I2C Motor
   * Driver.
   *
   * For stepper operation, this driver can run in one of two modes -
   * Mode 1, where this driver handles the stepping operation, and
   * Mode 2, where this driver simply sends commands to the Grove
   * Motor Driver, and it handles the stepping operation.  Mode2
   * requires updated (and working) firmware to be loaded onto the
   * device.
   *
   * The default stepper operation mode is Mode1, which is generally
   * more flexible and is supported on all firmware revisions.
   *
   * @image html grovemd.jpg
   * An example showing the use of a DC motor
   * @snippet grovemd.cxx Interesting
   * An example showing the use of a 4-wire stepper
   * @snippet grovemd-stepper.cxx Interesting
   */
  class GroveMD {

  public:
    // GroveMD registers
    typedef enum { SET_SPEED           = 0x82,
                   SET_PWM_FREQ        = 0x84,
                   SET_DIRECTION       = 0xaa,
                   SET_MOTOR_A         = 0xa1, // not documented
                   SET_MOTOR_B         = 0xa5, // not documented
                   STEPPER_ENABLE      = 0x1a, 
                   STEPPER_DISABLE     = 0x1b,
                   STEPPER_NUM_STEPS   = 0x1c
    } REG_T;

    // legal directions for the stepper
    typedef enum { STEP_DIR_CCW    = 0x01,
                   STEP_DIR_CW     = 0x00
    } STEP_DIRECTION_T;
    
    // legal directions for individual DC motors
    typedef enum { DIR_CCW    = 0x02,
                   DIR_CW     = 0x01
    } DC_DIRECTION_T;
    
    // stepper modes
    typedef enum { STEP_MODE1 = 0x00,
                   STEP_MODE2 = 0x01
    } STEP_MODE_T;
    
    /**
     * GroveMD constructor
     *
     * @param bus I2C bus to use
     * @param address I2C address to use
     */
    GroveMD(int bus=GROVEMD_I2C_BUS, 
            uint8_t address=GROVEMD_DEFAULT_I2C_ADDR);

    /**
     * GroveMD destructor
     */
    ~GroveMD();

    /**
     * Composes and writes a 3-byte packet to the controller
     *
     * @param reg Register location
     * @param data1 First byte of data
     * @param data2 Second byte of data
     * @return True if successful
     */
    bool writePacket(REG_T reg, uint8_t data1, uint8_t data2);

    /**
     * To control DC motors, sets the speed of motors A & B.
     * Valid values are 0-255.
     *
     * @param speedA Speed of motor A
     * @param speedB Speed of motor B
     * @return True if successful
     */
    bool setMotorSpeeds(uint8_t speedA, uint8_t speedB);

    /**
     * To control DC motors, sets the PWM frequency prescale
     * factor. Note: this register is not ducumented other than to say
     * the default value is 0x03. Presumably, this is the timer
     * prescale factor used on the ATMega MCU timer driving the PWM.
     *
     * @param freq PWM prescale frequency; default is 0x03
     * @return True if successful
     */
    bool setPWMFrequencyPrescale(uint8_t freq=0x03);

    /**
     * To control DC motors, sets the directions of motors A & B
     *
     * @param dirA Direction for motor A, DIR_CW or DIR_CCW
     * @param dirB Direction for motor B, DIR_CW or DIR_CCW
     * @return True if successful
     */
    bool setMotorDirections(DC_DIRECTION_T dirA, DC_DIRECTION_T dirB);

    /**
     * To control a stepper motor, sets its direction and speed, and
     * then starts operation.  For Mode2, this method will return
     * immediately.  For Mode1 (the default) this method returns when
     * the number of steps specified by setStepperSteps() has
     * completed.
     *
     * @param dir Direction, STEP_DIR_CW or STEP_DIR_CCW
     * @param speed Motor speed. Valid range is 1-255. For Mode 1
     * (default), this specifies the speed in RPM's.  For Mode 2,
     * speed is multiplied by 4ms by the board, so higher numbers
     * will mean a slower speed.
     * @return True if successful
     */
    bool enableStepper(STEP_DIRECTION_T dir, uint8_t speed);

    /**
     * To control a stepper motor, stops the stepper motor.
     *
     * @return True if successful
     */
    bool disableStepper();

    /**
     * To control a stepper motor, specifies the number of steps to
     * execute. For Mode2, valid values are between 1-255, 255 means
     * continuous rotation.
     *
     * For Mode1 (the default) steps can be any positive integer.
     *
     * @param steps Number of steps to execute. 255 (only in Mode2)
     * means continuous rotation.  
     * @return True if successful
     */
    bool setStepperSteps(unsigned int steps);

    /**
     * Configure the initial Stepper parameters.  This should be
     * called before any other stepper method.
     *
     * @param stepsPerRev The number of steps required to complete one
     * full revolution.
     * @param mode The stepper operating mode, default STEP_MODE1
     * @return Elapsed milliseconds
     */
    void configStepper(unsigned int stepsPerRev, STEP_MODE_T mode=STEP_MODE1);

  protected:
    mraa::I2c m_i2c;
    uint8_t m_addr;

  private:
    // steps per revolution
    int m_stepsPerRev;
    int m_currentStep;
    uint32_t m_stepDelay;
    uint32_t m_totalSteps;
    STEP_MODE_T m_stepMode;

    /**
     * Steps the motor one tick
     *
     */
    void stepperStep();

    // step direction: - 1 = forward, -1 = backward
    int m_stepDirection;

    // This is a NOOP value used to pad packets
    static const uint8_t GROVEMD_NOOP = 0x01;
    // our timer
    struct timeval m_startTime;

    /**
     * Returns the number of milliseconds elapsed since initClock()
     * was last called.
     *
     * @return Elapsed milliseconds
     */
    uint32_t getMillis();

    /**
     * Resets the clock
     *
     */
    void initClock();

  };
}