Read button to toggle LED

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main.cpp

00001 /*******************************************************************************
00002 * This program demonstrates how to read a switch and toggle a LED.             *
00003 * Connect LED and resistor between to DIP36 (P0_21) and DIP1 (0V).             *
00004 * Connect switch between DIP5 (P0_9) and DIP1 (0V).                            *
00005 *                                                                              *
00006 * Jon Fuge                                                                     *
00007 * V1.0 12/11/2013 First issue of code                                          *
00008 *******************************************************************************/
00009 
00010 #include "mbed.h" // has prototypes for DigitalIn and DigitalOut
00011 
00012 DigitalIn  mybutton(P0_9); // mybutton reads bit  9 of port 0 (DIP5).
00013 DigitalOut myled(P0_21);   // myled controls bit 21 of port 0 (DIP36).
00014 
00015 int main() {
00016    mybutton.mode(PullUp); // Configure pin to be a pull‐up input
00017    for(;;) { //Create infinite loop to keep program running.
00018       if (mybutton == 0) { // if mybutton = 0, then it has been pressed
00019          myled = !myled; // myled will now become !myled (! means NOT).
00020          wait(0.1); // Wait for 0.1 seconds to "debounce" the switch.
00021          while (mybutton == 0) {} // Wait for my button to be released.
00022       } // End of if (mybutton == 0)
00023    } // End of for(;;)
00024 } // end of int main()