Andrew Ferguson / Mbed 2 deprecated Ferguson_A2_Digital_Input

Program follows assignment specifications. Counter counts each switch state change so ten counts is only five button presses and releases. Wait function is used to avoid counting switch bounces.

Dependencies:   mbed

Files at this revision

API Documentation at this revision

Revision 3:896a932d47fc, committed 2022-10-06

Comitter:
a_ferguson
Date:
Thu Oct 06 16:36:02 2022 +0000
Parent:
2:af576070220a
Commit message:
Complete version to be graded (fixed switch bouncing issue)

Changed in this revision

main.cpp Show annotated file Show diff for this revision Revisions of this file 
--- a/main.cpp	Thu Oct 06 14:44:47 2022 +0000
+++ b/main.cpp	Thu Oct 06 16:36:02 2022 +0000
@@ -1,25 +1,30 @@
 #include "mbed.h"
 
-Serial pc(USBTX,USBRX); //do not need when we aren't communicating with pc
-DigitalOut myled1(LED1);
+Serial pc(USBTX,USBRX); // do not need when we aren't communicating with pc
+DigitalOut myled1(LED1); //LEDs 1 and 2
 DigitalOut myled2(LED2);
 DigitalIn button(p17); // button attached to p17
+Timer led2timer; // create timer
 
 int main() {
 
-int currentstate=0;
+int currentstate=0; // set variables as integers
 int previousstate=0;
 int counter=0;
 
+led2timer.start(); // starts timer
+
     while(1) {
         
         currentstate=button.read(); // set current state
         
-        if (currentstate==1){ //blinks 1s interval when pressed
-            myled2=!myled2;
-            wait(1);
+        if (currentstate==1){ // button pressed
+            if (led2timer.read()>=1){ // blinks 1s interval when pressed
+                myled2=!myled2;
+                led2timer.reset(); // reset timer
+                }
             
-            if (currentstate==previousstate){
+            if (currentstate==previousstate){ // no change
                 }
                 
             else{ // change in state adds counter
@@ -27,13 +32,15 @@
                 pc.printf("count=%i \r\n",counter);
                 }
                 
-            } //if
+            } // if
             
-        else { //blinks 0.3s interval when released
-            myled2=!myled2;
-            wait(0.3);
+        else { // button released
+            if (led2timer.read()>=0.3){ // blinks 0.3s interval when released
+                myled2=!myled2;
+                led2timer.reset(); // reset timer
+                }
             
-            if (currentstate==previousstate){
+            if (currentstate==previousstate){ // no change
                 }
                 
             else{ // change in state adds counter
@@ -41,14 +48,17 @@
                 pc.printf("count=%i \r\n",counter);
                 }
             
-            } //else
+            } // else
         
         if (counter==10){ // counter reaches 10 turns on led1
             myled1=1;
-            } //if
+            } // if
         
-        previousstate=currentstate; //set previous state
+        previousstate=currentstate; //set previous state at loop end
         
-    } //while
+        wait(0.1); // prevents the counter from counting switch bounces
+                   // wait is ok because it it shorter than the timer 0.3
+        
+    } // while
     
-} //main
+} // main