example.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 #ifdef PINDETECT_EXAMPLE_COMPILE
00024 
00025 #include "mbed.h"
00026 #include "PinDetect.h"
00027 
00028 PinDetect  pin ( p21  );
00029 DigitalOut led1( LED1 );
00030 DigitalOut led2( LED2 );
00031 DigitalOut led3( LED3 );
00032 DigitalOut led4( LED4 );
00033 
00034 /*
00035  * Note, the PinDetect can be defined thus:-
00036  *     PinDetect pin( p21, PullDown );
00037  * This allows you to specify the DigitalIn pinmode
00038  * when you create the PinDetect object. This means
00039  * using pin.mode() later is then no longer required.
00040  */
00041 
00042 // C function callbacks follow.
00043 
00044 void keyPressed( void ) {
00045     led2 = 1;
00046     led3 = 0;
00047     led4 = 0;
00048 }
00049 
00050 void keyReleased( void ) {
00051     led2 = 0;
00052     led3 = 0;
00053     led4 = 0;
00054 }
00055 
00056 void keyPressedHeld( void ) {
00057     led3 = 1;
00058 }
00059 
00060 void keyReleasedHeld( void ) {
00061     led4 = 1;
00062 }
00063 
00064 // The main program.
00065 
00066 int main() {
00067 
00068     pin.mode( PullDown );
00069     pin.attach_asserted( &keyPressed );
00070     pin.attach_deasserted( &keyReleased );
00071     pin.attach_asserted_held( &keyPressedHeld );
00072     
00073     // This callback will often be of little use as it's
00074     // called after every assertion/deassertion. However,
00075     // it's provided for completeness. You may find a use
00076     // for it. If not, just don't attach a callback and it
00077     // will not activate.
00078     pin.attach_deasserted_held( &keyReleasedHeld );
00079     
00080     // You can define how many continuous samples must be
00081     // asserted before the attach_asserted() function is called.
00082     //     pin.setSamplesTillAssert( 10 );
00083     // This would mean 10 * 20ms debounce time = 200ms.
00084 
00085     // You can define how many continuous samples must be
00086     // asserted before the attach_asserted_held() function is called.
00087     //     pin.setSamplesTillHeld( 200 );
00088     // This would mean 200 * 20ms debounce time = 2seconds.
00089 
00090     // By default, "asserted" assumes the pin going high from 0volts to 5volts
00091     // and deasserted assumes going from 5volts to 0volts. You can invert this
00092     // logic so that going to 0volts is asserted and going to 5volts is deasserted
00093     // using this setup function:-
00094     //     pin.setAssertValue( 0 );
00095 
00096     // Sampling does NOT begin until you set the frequency. So, until
00097     // you call this function NO callbacks will be made. With no arguments
00098     // passed the default is 20000 microseconds (20ms). Specifiy the sampling
00099     // period in microseconds if you want a different value to 20ms.
00100     // For example, for a sampling period of 10ms do:-
00101     //     pin.setSampleFrequency( 10000 );
00102     // Note, if you change the sampling frequency you will probably also
00103     // want to change the number of samples till assert and held as show
00104     // above.
00105     pin.setSampleFrequency(); // Defaults to 20ms.
00106 
00107     while( 1 ) {
00108         led1 = !led1;
00109         wait( 0.2 );
00110     }
00111 }
00112 
00113 #endif