Diff: inc/SimpleServoControl.h

Revision:

2:d6a018232650

diff -r fbb8acf19e77 -r d6a018232650 inc/SimpleServoControl.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/inc/SimpleServoControl.h	Thu May 19 22:46:09 2011 +0000
@@ -0,0 +1,119 @@
+/*
+    Copyright (c) 2011 Andy Kirkham
+ 
+    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.
+*/
+
+// Derived from forum post http://mbed.org/forum/helloworld/topic/2303
+
+#ifndef AJK_SIMPLESERVOCONTROL_H
+#define AJK_SIMPLESERVOCONTROL_H
+
+#include "mbed.h"
+#include "SimpleRCservos.h"
+
+namespace AjK {
+
+/** SimpleServoControl
+ *
+ * Very simple servo controller class.
+ * 
+ * @see http://mbed.org/forum/helloworld/topic/2303
+ */
+class SimpleServoControl {
+
+protected:
+    double _current_position;
+    double _desired_position;
+    double _step;
+    int    _poll_interval;
+    SimpleRCservos::Servo _motor;
+    SimpleRCservos *_servos;
+    Ticker _servo_poll;
+    
+public:
+
+    // Constructor.
+    SimpleServoControl(SimpleRCservos *servos, SimpleRCservos::Servo motor, double min = -90.0, double max = +90.0) 
+    { 
+        _servos = servos;
+        _motor = motor; 
+        _servos->setLimits(_motor, min, max); // define logical limits.
+        _servos->enable(_motor); // Enable the PWM outout.
+        _current_position = 0.0;
+        _desired_position = 0.0;
+        _step = 1.0;
+        _poll_interval = 10000; // 100ms.
+        _servo_poll.attach_us(this, &SimpleServoControl::poll, _poll_interval); 
+    }
+    
+    void poll(void) 
+    {
+        if (_desired_position > _current_position) {
+            _current_position += _step;
+            // Don't allow the servo to oscillate around _desired_position.
+            if (_desired_position < _current_position) { 
+                _current_position = _desired_position; 
+            }
+            _servos->position(_motor, _current_position);                        
+        }
+        else if (_desired_position < _current_position) {
+            _current_position -= _step;
+            // Don't allow the servo to oscillate around _desired_position.
+            if (_desired_position > _current_position) {
+                _current_position = _desired_position; 
+            }
+            _servos->position(_motor, _current_position);            
+        }
+    }
+    
+    void position(double position = 90.0)  // spins the servo 90º to the left
+    {
+        _desired_position = position;
+    }
+    
+    void setStep(double d) 
+    { 
+        _step = d; 
+    }
+    
+    double getStep(void) 
+    { 
+        return _step; 
+    } 
+    
+    void setPollInterval(int i) 
+    { 
+        _poll_interval = i;
+        _servo_poll.detach();
+        _servo_poll.attach_us(this, &SimpleServoControl::poll, _poll_interval); 
+    }
+    
+    int getPollInterval(void) 
+    { 
+        return _poll_interval; 
+    }
+    
+};
+
+}; // namespace AjK ends.
+
+using namespace AjK;
+
+#endif