Sally Brown / RenBed_Tutorial2

Read button to toggle LED

main.cpp@0:131ad5c8b45a, 2014-02-07 (annotated)

Committer:
salatron
Date:
Fri Feb 07 10:17:57 2014 +0000
Revision:
0:131ad5c8b45a
Read Button

Who changed what in which revision?

UserRevisionLine numberNew contents of line
salatron 0:131ad5c8b45a 1 /*******************************************************************************
salatron 0:131ad5c8b45a 2 * This program demonstrates how to read a switch and toggle a LED. *
salatron 0:131ad5c8b45a 3 * Connect LED and resistor between to DIP36 (P0_21) and DIP1 (0V). *
salatron 0:131ad5c8b45a 4 * Connect switch between DIP5 (P0_9) and DIP1 (0V). *
salatron 0:131ad5c8b45a 5 * *
salatron 0:131ad5c8b45a 6 * Jon Fuge *
salatron 0:131ad5c8b45a 7 * V1.0 12/11/2013 First issue of code *
salatron 0:131ad5c8b45a 8 *******************************************************************************/
salatron 0:131ad5c8b45a 9
salatron 0:131ad5c8b45a 10 #include "mbed.h" // has prototypes for DigitalIn and DigitalOut
salatron 0:131ad5c8b45a 11
salatron 0:131ad5c8b45a 12 DigitalIn mybutton(P0_9); // mybutton reads bit 9 of port 0 (DIP5).
salatron 0:131ad5c8b45a 13 DigitalOut myled(P0_21); // myled controls bit 21 of port 0 (DIP36).
salatron 0:131ad5c8b45a 14
salatron 0:131ad5c8b45a 15 int main() {
salatron 0:131ad5c8b45a 16 mybutton.mode(PullUp); // Configure pin to be a pull‐up input
salatron 0:131ad5c8b45a 17 for(;;) { //Create infinite loop to keep program running.
salatron 0:131ad5c8b45a 18 if (mybutton == 0) { // if mybutton = 0, then it has been pressed
salatron 0:131ad5c8b45a 19 myled = !myled; // myled will now become !myled (! means NOT).
salatron 0:131ad5c8b45a 20 wait(0.1); // Wait for 0.1 seconds to "debounce" the switch.
salatron 0:131ad5c8b45a 21 while (mybutton == 0) {} // Wait for my button to be released.
salatron 0:131ad5c8b45a 22 } // End of if (mybutton == 0)
salatron 0:131ad5c8b45a 23 } // End of for(;;)
salatron 0:131ad5c8b45a 24 } // end of int main()