PinDetect.h

00001 /*
00002     Copyright (c) 2010 Andy Kirkham
00003 
00004     Permission is hereby granted, free of charge, to any person obtaining a copy
00005     of this software and associated documentation files (the "Software"), to deal
00006     in the Software without restriction, including without limitation the rights
00007     to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008     copies of the Software, and to permit persons to whom the Software is
00009     furnished to do so, subject to the following conditions:
00010 
00011     The above copyright notice and this permission notice shall be included in
00012     all copies or substantial portions of the Software.
00013 
00014     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015     IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016     FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017     AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018     LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019     OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00020     THE SOFTWARE.
00021 */
00022 
00023 #ifndef AJK_PIN_DETECT_H
00024 #define AJK_PIN_DETECT_H
00025 
00026 #ifndef MBED_H
00027     #include "mbed.h"
00028 #endif
00029 
00030 #ifndef PINDETECT_PIN_ASSERTED
00031     #define PINDETECT_PIN_ASSERTED   1
00032 #endif
00033 
00034 #ifndef PINDETECT_SAMPLE_PERIOD
00035     #define PINDETECT_SAMPLE_PERIOD 20000
00036 #endif
00037 
00038 #ifndef PINDETECT_ASSERT_COUNT
00039     #define PINDETECT_ASSERT_COUNT  1
00040 #endif
00041 
00042 #ifndef PINDETECT_HOLD_COUNT
00043     #define PINDETECT_HOLD_COUNT    50
00044 #endif
00045 
00046 namespace AjK {
00047 
00048 class PinDetect {
00049   public:
00050     friend class Ticker;
00051 
00052 
00053     /** PinDetect constructor
00054      *
00055      * By default the PinMode is set to PullDown.
00056      *
00057      * @see http://mbed.org/handbook/DigitalIn
00058      * @param p PinName is a valid pin that supports DigitalIn
00059      */
00060     PinDetect(PinName p);
00061 
00062     /** PinDetect constructor
00063      *
00064      * @see http://mbed.org/handbook/DigitalIn
00065      * @param PinName p is a valid pin that supports DigitalIn
00066      * @param PinMode m The mode the DigitalIn should use.
00067      */
00068     PinDetect(PinName p, PinMode m);
00069 
00070     /** PinDetect destructor
00071      */
00072     virtual ~PinDetect(void);
00073 
00074     /** Set the sampling time in microseconds.
00075      *
00076      * @param int The time between pin samples in microseconds.
00077      */
00078     void setSampleFrequency(int i = PINDETECT_SAMPLE_PERIOD);
00079 
00080     /** Set the value used as assert.
00081      *
00082      * Defaults to 1 (ie if pin == 1 then pin asserted).
00083      *
00084      * @param int New assert value (1 or 0)
00085      */
00086     void setAssertValue(int i = PINDETECT_PIN_ASSERTED);
00087 
00088     /** Set the number of continuous samples until assert assumed.
00089      *
00090      * Defaults to 1 (1 * sample frequency).
00091      *
00092      * @param int The number of continuous samples until assert assumed.
00093      */
00094     void setSamplesTillAssert(int i);
00095 
00096     /** Set the number of continuous samples until held assumed.
00097      *
00098      * Defaults to 50 * sample frequency.
00099      *
00100      * @param int The number of continuous samples until held assumed.
00101      */
00102     void setSamplesTillHeld(int i);
00103 
00104     /** Set the pin mode.
00105      *
00106      * @see http://mbed.org/projects/libraries/api/mbed/trunk/DigitalInOut#DigitalInOut.mode
00107      * @param PinMode m The mode to pass on to the DigitalIn
00108      */
00109     void mode(PinMode m);
00110 
00111     void attach_asserted(Callback<void()> function);
00112 
00113     void attach_deasserted(Callback<void()> function);
00114 
00115     void attach_asserted_held(Callback<void()> function);
00116 
00117     void attach_deasserted_held(Callback<void()> function);
00118 
00119     /** operator int()
00120      *
00121      * Read the value of the pin being sampled.
00122      */
00123     operator int() {
00124         return _in->read();
00125     }
00126 
00127   protected:
00128     DigitalIn   *_in;
00129     Ticker      *_ticker;
00130     int         _prevState;
00131     int         _currentStateCounter;
00132     int         _sampleTime;
00133     int         _assertValue;
00134     int         _samplesTillAssertReload;
00135     int         _samplesTillAssert;
00136     int         _samplesTillHeldReload;
00137     int         _samplesTillHeld;
00138     Callback<void()> _callbackAsserted;
00139     Callback<void()> _callbackDeasserted;
00140     Callback<void()> _callbackAssertedHeld;
00141     Callback<void()> _callbackDeassertedHeld;
00142 
00143     /** The Ticker periodic callback function
00144       */
00145     void isr(void);
00146 
00147     /** initialise class
00148      *
00149      * @param PinName p is a valid pin that supports DigitalIn
00150      * @param PinMode m The mode the DigitalIn should use.
00151      */
00152     void init(PinName p, PinMode m);
00153 };
00154 
00155 }; // namespace AjK ends.
00156 
00157 using namespace AjK;
00158 
00159 #endif