Andrew Ferguson / Mbed 2 deprecated Ferguson_A2_Digital_Input

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Dependencies:   mbed

main.cpp@3:896a932d47fc, 2022-10-06 (annotated)

Committer:
a_ferguson
Date:
Thu Oct 06 16:36:02 2022 +0000
Revision:
3:896a932d47fc
Parent:
2:af576070220a 
Complete version to be graded (fixed switch bouncing issue)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
a_ferguson 0:1cf58db95ce6 1 #include "mbed.h"
a_ferguson 0:1cf58db95ce6 2
a_ferguson 3:896a932d47fc 3 Serial pc(USBTX,USBRX); // do not need when we aren't communicating with pc
a_ferguson 3:896a932d47fc 4 DigitalOut myled1(LED1); //LEDs 1 and 2
a_ferguson 1:c186d9b63164 5 DigitalOut myled2(LED2);
a_ferguson 0:1cf58db95ce6 6 DigitalIn button(p17); // button attached to p17
a_ferguson 3:896a932d47fc 7 Timer led2timer; // create timer
a_ferguson 0:1cf58db95ce6 8
a_ferguson 0:1cf58db95ce6 9 int main() {
a_ferguson 0:1cf58db95ce6 10
a_ferguson 3:896a932d47fc 11 int currentstate=0; // set variables as integers
a_ferguson 2:af576070220a 12 int previousstate=0;
a_ferguson 2:af576070220a 13 int counter=0;
a_ferguson 2:af576070220a 14
a_ferguson 3:896a932d47fc 15 led2timer.start(); // starts timer
a_ferguson 3:896a932d47fc 16
a_ferguson 0:1cf58db95ce6 17 while(1) {
a_ferguson 2:af576070220a 18
a_ferguson 2:af576070220a 19 currentstate=button.read(); // set current state
a_ferguson 2:af576070220a 20
a_ferguson 3:896a932d47fc 21 if (currentstate==1){ // button pressed
a_ferguson 3:896a932d47fc 22 if (led2timer.read()>=1){ // blinks 1s interval when pressed
a_ferguson 3:896a932d47fc 23 myled2=!myled2;
a_ferguson 3:896a932d47fc 24 led2timer.reset(); // reset timer
a_ferguson 3:896a932d47fc 25 }
a_ferguson 2:af576070220a 26
a_ferguson 3:896a932d47fc 27 if (currentstate==previousstate){ // no change
a_ferguson 2:af576070220a 28 }
a_ferguson 2:af576070220a 29
a_ferguson 2:af576070220a 30 else{ // change in state adds counter
a_ferguson 2:af576070220a 31 counter=counter+1;
a_ferguson 2:af576070220a 32 pc.printf("count=%i \r\n",counter);
a_ferguson 2:af576070220a 33 }
a_ferguson 2:af576070220a 34
a_ferguson 3:896a932d47fc 35 } // if
a_ferguson 2:af576070220a 36
a_ferguson 3:896a932d47fc 37 else { // button released
a_ferguson 3:896a932d47fc 38 if (led2timer.read()>=0.3){ // blinks 0.3s interval when released
a_ferguson 3:896a932d47fc 39 myled2=!myled2;
a_ferguson 3:896a932d47fc 40 led2timer.reset(); // reset timer
a_ferguson 3:896a932d47fc 41 }
a_ferguson 2:af576070220a 42
a_ferguson 3:896a932d47fc 43 if (currentstate==previousstate){ // no change
a_ferguson 2:af576070220a 44 }
a_ferguson 2:af576070220a 45
a_ferguson 2:af576070220a 46 else{ // change in state adds counter
a_ferguson 2:af576070220a 47 counter=counter+1;
a_ferguson 2:af576070220a 48 pc.printf("count=%i \r\n",counter);
a_ferguson 2:af576070220a 49 }
a_ferguson 2:af576070220a 50
a_ferguson 3:896a932d47fc 51 } // else
a_ferguson 2:af576070220a 52
a_ferguson 2:af576070220a 53 if (counter==10){ // counter reaches 10 turns on led1
a_ferguson 2:af576070220a 54 myled1=1;
a_ferguson 3:896a932d47fc 55 } // if
a_ferguson 2:af576070220a 56
a_ferguson 3:896a932d47fc 57 previousstate=currentstate; //set previous state at loop end
a_ferguson 2:af576070220a 58
a_ferguson 3:896a932d47fc 59 wait(0.1); // prevents the counter from counting switch bounces
a_ferguson 3:896a932d47fc 60 // wait is ok because it it shorter than the timer 0.3
a_ferguson 3:896a932d47fc 61
a_ferguson 3:896a932d47fc 62 } // while
a_ferguson 2:af576070220a 63
a_ferguson 3:896a932d47fc 64 } // main