Diff: BBTrackball.h

Revision:

0:ad0f8a08c470

Child:

1:94c8e1e74dc1

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/BBTrackball.h	Thu Dec 08 07:29:12 2011 +0000
@@ -0,0 +1,141 @@
+/* Copyright 2011 Adam Green (http://mbed.org/users/AdamGreen/)
+
+   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.
+*/
+/* Header file for class to control Sparkfun's Blackberry Trackball:
+     http://www.sparkfun.com/products/9320
+*/
+#ifndef _BBTRACKBALL_H_
+#define _BBTRACKBALL_H_
+#include <mbed.h>
+
+namespace AFP 
+{
+
+/** A class to interface with the Sparkfun Blackberry Trackball Breakout Board.
+ *  http://www.sparkfun.com/products/9320
+ *
+ *  This breakout board uses a hall effect for each direction of motion (up, 
+ *  down, left, right) and generates pulses as the trackball is rotated in each
+ *  of these directions.  This class counts both the rising and falling edges
+ *  of these pulses in an interrupt handler.  The main program can query for
+ *  the number of pulses that have been generated since the previous query was
+ *  made.
+ *
+ *  The breakout board also has a push button placed beneath the trackball so
+ *  that user presses can be detected as well.  This class will provide the
+ *  state of this button as well after filtering it for the purpose of 
+ *  debouncing.
+ *
+ *  The last feature of this breakout board that is supported by the class
+ *  includes the 4 LEDs that have been placed beneath the trackball.  This
+ *  class allows the caller to specify an individual brightness value for each
+ *  of the LEDs (red, blue, green, white). 
+ *
+ * Example:
+ * @code
+#include <mbed.h>
+#include "BBTrackball.h"
+
+int main() 
+{
+    // UNDONE: Add something to this section.
+    return 0;
+}
+ * @endcode
+ */
+class CBBTrackball
+{
+public:
+     /** A structure in which the current state of the trackball is returned
+         from the GetState() method.
+         
+         @see GetState()
+     */
+     struct SState
+     {
+        int     ButtonPressed;  /**< 1 if the button is currently pressed and 0 otherwise. */
+        short   Up;             /**< Number of upward pulses since last call. */
+        short   Down;           /**< Number of downward pulses since last call. */
+        short   Left;           /**< Number of leftward pulses since last call. */
+        short   Right;          /**< Number of rightward pulses since last call. */
+     };
+     
+     /**
+     * Creates a CBBTrackball object.
+     *
+     * Create a CBBTrackball object, binds it to the specified input/output
+     * pins, and initializes the required interrupt handling.
+     *
+     * @param BluePin The mbed pin which is connected to the BLU pin of the breakout board.
+     * @param RedPin The mbed pin which is connected to the RED pin of the breakout board.
+     * @param GreenPin The mbed pin which is connected to the GRN pin of the breakout board.
+     * @param WhitePin The mbed pin which is connected to the WHT pin of the breakout board.
+     * @param UpPin The mbed pin which is connected to the UP pin of the breakout board.
+     * @param DownPin The mbed pin which is connected to the DWN pin of the breakout board.
+     * @param LeftPin The mbed pin which is connected to the LFT pin of the breakout board.
+     * @param RightPin The mbed pin which is connected to the RHT pin of the breakout board.
+     * @param ButtonPin The mbed pin which is connected to the BTN pin of the breakout board.
+     */
+    CBBTrackball(PinName BluePin,
+                 PinName RedPin,
+                 PinName GreenPin,
+                 PinName WhitePin,
+                 PinName UpPin,
+                 PinName DownPin,
+                 PinName LeftPin,
+                 PinName RightPin,
+                 PinName ButtonPin) : m_UpInterrupt(UpPin),
+                                      m_DownInterrupt(DownPin),
+                                      m_LeftInterrupt(LeftPin),
+                                      m_RightInterrupt(RightPin),
+                                      m_UpCount(0),
+                                      m_DownCount(0),
+                                      m_LeftCount(0),
+                                      m_RightCount(0)
+    {
+        m_UpInterrupt.rise<CBBTrackball>(this, &CBBTrackball::UpISR);
+        m_DownInterrupt.rise<CBBTrackball>(this, &CBBTrackball::DownISR);
+        m_LeftInterrupt.rise<CBBTrackball>(this, &CBBTrackball::LeftISR);
+        m_RightInterrupt.rise<CBBTrackball>(this, &CBBTrackball::RightISR);
+    }
+    
+    
+    /** Gets current state.
+    *
+    * @param pState points to the structure to be filled in with the current state.
+    */
+    void GetState(SState* pState);
+    
+                     
+protected:
+    void UpISR(void);
+    void DownISR(void);
+    void LeftISR(void);
+    void RightISR(void);
+    
+    InterruptIn     m_UpInterrupt;
+    InterruptIn     m_DownInterrupt;
+    InterruptIn     m_LeftInterrupt;
+    InterruptIn     m_RightInterrupt;  
+    
+    int             m_UpCount;
+    int             m_DownCount;
+    int             m_LeftCount;
+    int             m_RightCount;        
+};
+
+} // namespace AFP
+using namespace AFP;
+
+#endif /* _BBTRACKBALL_H__BBTRACKBALL_H_ */