File content as of revision 0:edc152f119b7:

 /*motor driver libary modified from the following libary,
 *  
 * mbed simple H-bridge motor controller
 * Copyright (c) 2007-2010, sford
 * 
 * by Christopher Hasler.
 * 
 * from sford's libary,
 *
 * 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.
 */

#include "motordriver.h"
 
#include "mbed.h"
 
Motor::Motor(PinName pwm, PinName fwd, PinName rev, int brakeable):
        _pwm(pwm), _fwd(fwd), _rev(rev) {

    // Set initial condition of PWM
    _pwm.period(0.001);
    _pwm = 0;

    // Initial condition of output enables
    _fwd = 0;
    _rev = 0;
    
    //set if the motor dirver is capable of braking. (addition)
    Brakeable= brakeable;
}
 
void Motor::speed(float speed) {
    _fwd = (speed > 0.0);
    _rev = (speed < 0.0);
    _pwm = abs(speed);
}
//  (additions)
void Motor::coast(void) {
    _fwd = 0;
    _rev = 0;
    _pwm = 0;
}

void Motor::stop(void) {
    if (Brakeable == 1) {
        _fwd = 1;
        _rev = 1;
        _pwm = 0.5;
    }
    else
    return;
}
        
/*
 test code, this demonstrates working motor drivers.
 
Motor A(p22, p6, p5, 1); // pwm, fwd, rev, can break 
Motor B(p21, p7, p8, 1); // pwm, fwd, rev, can break
int main() {
    for (float s=-1.0; s < 1.0 ; s += 0.01) {
       A.speed(s); 
       B.speed(s); 
       wait(0.02);
    }
    A.stop();
    B.stop();
    wait(1);
    A.coast();
    B.coast();
}
*/