motor drive libary to use speed control, coasting and dynamic braking. NOTE, dynamic braking my result in large currents. this may or may not set the motor driver on fire/break it/other undesired effects. so read the data sheet folks.

Dependents:   Test

Fork of Motordriver by Christopher Hasler

Revision:
0:edc152f119b7
Child:
1:3da7302dc9ae
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/motordriver.cpp	Sat Nov 06 13:05:17 2010 +0000
@@ -0,0 +1,87 @@
+ /*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();
+}
+*/
\ No newline at end of file