Revision 0:5490c22f727d, committed 2011-02-22

Comitter:

cr0n0s20

Date:

Tue Feb 22 22:07:28 2011 +0000

Commit message:

1.0

Changed in this revision

diff -r 000000000000 -r 5490c22f727d Servo.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Servo.cpp	Tue Feb 22 22:07:28 2011 +0000
@@ -0,0 +1,74 @@
+/* mbed R/C Servo Library
+ *  
+ * Copyright (c) 2007-2010 sford, cstyles
+ *
+ * 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 "Servo.h"
+#include "mbed.h"
+
+static float clamp(float value, float min, float max) {
+    if(value < min) {
+        return min;
+    } else if(value > max) {
+        return max;
+    } else {
+        return value;
+    }
+}
+
+Servo::Servo(PinName pin) : _pwm(pin) {
+    calibrate();
+    write(0.5);
+}
+
+void Servo::write(float percent) {
+    float offset = _range * 2.0 * (percent - 0.5);
+    _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range));
+    _p = clamp(percent, 0.0, 1.0);
+}
+
+void Servo::position(float degrees) {
+    float offset = _range * (degrees / _degrees);
+    _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range));
+}
+
+void Servo::calibrate(float range, float degrees) {
+    _range = range;
+    _degrees = degrees;
+}
+
+float Servo::read() {
+    return _p;
+}
+
+Servo& Servo::operator= (float percent) { 
+    write(percent);
+    return *this;
+}
+
+Servo& Servo::operator= (Servo& rhs) {
+    write(rhs.read());
+    return *this;
+}
+
+Servo::operator float() {
+    return read();
+}

diff -r 000000000000 -r 5490c22f727d Servo.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Servo.h	Tue Feb 22 22:07:28 2011 +0000
@@ -0,0 +1,98 @@
+/* mbed R/C Servo Library
+ * Copyright (c) 2007-2010 sford, cstyles
+ *
+ * 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.
+ */
+  
+#ifndef MBED_SERVO_H
+#define MBED_SERVO_H
+
+#include "mbed.h"
+
+/** Servo control class, based on a PwmOut
+ *
+ * Example:
+ * @code
+ * // Continuously sweep the servo through it's full range
+ * #include "mbed.h"
+ * #include "Servo.h"
+ * 
+ * Servo myservo(p21);
+ * 
+ * int main() {
+ *     while(1) {
+ *         for(int i=0; i<100; i++) {
+ *             myservo = i/100.0;
+ *             wait(0.01);
+ *         }
+ *         for(int i=100; i>0; i--) {
+ *             myservo = i/100.0;
+ *             wait(0.01);
+ *         }
+ *     }
+ * }
+ * @endcode
+ */
+class Servo {
+
+public:
+    /** Create a servo object connected to the specified PwmOut pin
+     *
+     * @param pin PwmOut pin to connect to 
+     */
+    Servo(PinName pin);
+    
+    /** Set the servo position, normalised to it's full range
+     *
+     * @param percent A normalised number 0.0-1.0 to represent the full range.
+     */
+    void write(float percent);
+    
+    /**  Read the servo motors current position
+     *
+     * @param returns A normalised number 0.0-1.0  representing the full range.
+     */
+    float read();
+    
+    /** Set the servo position
+     *
+     * @param degrees Servo position in degrees
+     */
+    void position(float degrees);
+    
+    /**  Allows calibration of the range and angles for a particular servo
+     *
+     * @param range Pulsewidth range from center (1.5ms) to maximum/minimum position in seconds
+     * @param degrees Angle from centre to maximum/minimum position in degrees
+     */
+    void calibrate(float range = 0.0005, float degrees = 45.0); 
+        
+    /**  Shorthand for the write and read functions */
+    Servo& operator= (float percent);
+    Servo& operator= (Servo& rhs);
+    operator float();
+
+protected:
+    PwmOut _pwm;
+    float _range;
+    float _degrees;
+    float _p;
+};
+
+#endif