Diff: ArduinoMotorShield.hpp

Revision:

0:27f8679b31e5

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ArduinoMotorShield.hpp	Wed Feb 12 22:56:17 2014 +0000
@@ -0,0 +1,129 @@
+/**
+   @file
+   @brief Class to abstract the interface to an Arduino Motor Shield R3
+          See http://arduino.cc/en/Main/ArduinoMotorShieldR3
+   
+   @author John Bailey 
+
+   @copyright Copyright 2014 John Bailey
+
+   @section LICENSE
+   
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+*/
+
+#if !defined ARDUINOMOTORSHIELD_HPP
+#define      ARDUINOMOTORSHIELD_HPP
+
+#include "mbed.h"
+#include <stdint.h>
+
+/** Class to abstract the interface to an Arduino Motor Shield R3
+    See http://arduino.cc/en/Main/ArduinoMotorShieldR3
+    
+    This class is a pretty thin wrapper around the analog inputs and 
+    digital outputs which interface to the motor drives
+    
+    Currently supports:
+        TARGET_KL46Z - Assumes the presence of the cross-wiring on PWM B 
+                       (see "Issues" at http://mbed.org/users/johnb/notebook/mutt-mbed-enabled-robot-vehicle/ )
+    
+    @todo Support for bipolar stepper motor
+    @todo Support for other targets
+*/
+class ArduinoMotorShield
+{    
+    public:
+    
+        typedef enum
+        {
+            MOTOR_FORWARD  = 0,
+            MOTOR_BACKWARD = 1
+        } MotorDirection_e;
+    
+        /** Enumeration to distinguish between the motors connected to the shield */    
+        typedef enum
+        {
+            /* Motor 'A' */
+            MOTOR_A = 0,
+            /* Motor 'A' */
+            MOTOR_B = 1
+        } Motor_e;
+    
+    protected:
+        /** Maximum number of motors which can be connected to the shield */
+        static const uint8_t MOTOR_DRIVE_COUNT = 2U;
+        
+        /** Maximum current (per motor drive) supported by the shield */
+        static const uint8_t MOTOR_MAX_CURRENT = 2U;
+    
+        PwmOut     m_a_motorControl;
+        PwmOut     m_b_motorControl;
+        DigitalOut m_a_brake;
+        DigitalOut m_b_brake;
+        AnalogIn   m_a_motorCurrent;
+        AnalogIn   m_b_motorCurrent;
+        DigitalOut m_a_motorDirection;    
+        DigitalOut m_b_motorDirection;    
+    
+        PwmOut     *m_motorControl[ MOTOR_DRIVE_COUNT ];
+        DigitalOut *m_brake[ MOTOR_DRIVE_COUNT ];
+        AnalogIn   *m_motorCurrent[ MOTOR_DRIVE_COUNT ];
+        DigitalOut *m_motorDirection[ MOTOR_DRIVE_COUNT ];
+        
+        float      m_speed[ MOTOR_DRIVE_COUNT ];
+        bool       m_motorForward[ MOTOR_DRIVE_COUNT ];
+    public:
+    
+        /** Constructor */
+        ArduinoMotorShield();
+        
+        /** Set the motor power (and direction) for the specified motor
+         
+            \param p_motor Use this parameter to specify which motor to set the power on
+            \param p_speed Set the power of the motor, ranging from -1 (full power, reverse direction) to
+                           +1 (full power, forward direction)
+        */
+        void SetMotorPower( const Motor_e p_motor, const float p_speed, bool p_force = false );
+        
+        /** Retrieve the current being consumed by the specified motor
+            \param p_motor The motor to retrieve the current for
+        */
+        float GetMotorCurrent( const Motor_e p_motor );
+        
+        /** Enable or disable the brake on the specified motor.  In the case that the braking
+            option is enabled then (when appropriate) the shield will actively brake the motor
+            rather than allowing it to coast down
+            
+            \param p_motor The motor to set the brake option for
+            \param p_enable Specify whether braking should be enabled or disabled */
+        void SetBrake( const Motor_e p_motor, bool p_enable );
+        
+        /** Set the virtual 'polarity' of a motor.  This allows you to swap the meaning of "forward"
+            with respect to the SetMotorPower() method.  For example:
+            
+                shield.SetMotorPolarity( MOTOR_A, MOTOR_FORWARD );
+                shield.SetMotorPower( MOTOR_A, 1.0F );
+                // This call will cause the motor to change direction !
+                shield.SetMotorPolarity( MOTOR_A, MOTOR_BACKWARD );
+                // No further change is caused by this call
+                shield.SetMotorPower( MOTOR_A, 1.0F );
+                
+            \param p_motor The motor to change the direction setting for
+            \param p_dir   The direction which "forward" should map to.
+        */
+        void SetMotorPolarity( const Motor_e p_motor, const MotorDirection_e p_dir );
+};
+
+#endif // !defined ARDUINOMOTORSHIELD_HPP
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