Diff: main.cpp

Revision:

5:c849e3c4a5f0

Parent:

4:43ce9b92ae68

Child:

6:dcc4031025a6

--- a/main.cpp	Tue Sep 12 12:58:40 2017 +0000
+++ b/main.cpp	Tue Sep 12 13:21:53 2017 +0000
@@ -1,50 +1,54 @@
 #include "mbed.h"
 /*
-    Serial2RGB main by C. S. Tritt, Last revised 3/18/17 (v. 1.1)
-    
-    Toggles RGB LED junctions in response to serial input. Echos input.
+    Serial2RGB main by C. S. Tritt, Last revised 9/12/17 (v. 1.2)
+
+    Toggles RGB LED junctions in response to serial input. Note input is case 
+    sensive and known "commands" are r (toggle red), g (toggle green) and b 
+    toggle blue). Input (including CR/LF is echoed.
     
     Suggested wiring...
-    
+
     Common Anode LED (active low)
-    
-                           /-- 680 kΩ -- D9 (red)
-    + 3.3 to 5.0 V ----LED<--- 680 Ω -- D10 (green)
-                           \-- 1 kΩ -- D11 (blue)
-    
+
+                           /-- 680 kΩ -- D13 (red)
+    + 3.3 to 5.0 V ----LED<--- 680 Ω -- D14 (green)
+                           \-- 1 kΩ -- D15 (blue)
+
     Common Cathode LED (active high)
-    
-                /-- 680 Ω -- D9 (red)
-    GND ----LED<--- 680 Ω -- D10 (green)
-                \-- 1 kΩ -- D11 (blue)
-   
+
+                /-- 680 Ω -- D13 (red)
+    GND ----LED<--- 680 Ω -- D14 (green)
+                \-- 1 kΩ -- D15 (blue)
+
 */
+
+// Construct resources.
+
 DigitalOut RedLED(D13); // Arduino Digital pin 13 on Nucleos.
 DigitalOut GrnLED(D14); // Arduino Digital pin 14.
 DigitalOut BluLED(D15); // Arduino Digital pin 15.
 
 Serial pc(USBTX, USBRX); // Default settings are 9600 Baud, 8-N-1.
 
-int main() {
-    
-    RedLED = 0;
+int main()
+{
+
+    RedLED = 0;  // Set pins to known state (junction on if active low).
     GrnLED = 0;
     BluLED = 0;
-    char letter;
-    
-    while(true) {
-        if (pc.readable()) {
-            letter = pc.getc();
-            pc.putc(letter);
-            if (letter == 'r') {
-                RedLED = !RedLED;
+    char letter;  // Declare variable to hold recieved characters.
+
+    while(true) {  // Main (infinite) loop.
+        if (pc.readable()) {  // Is there a character waiting? If so,
+            letter = pc.getc();  // Get it.
+            pc.putc(letter);  // Echo it.
+            if (letter == 'r') {  // Respond to known letters, ignore others.
+                RedLED = !RedLED;  // Toggle red.
+            } else if (letter == 'g') {
+                GrnLED = !GrnLED;  // Toggle green.
+            } else if (letter == 'b') {
+                BluLED = !BluLED;  // Toggle blue.
             }
-            else if (letter == 'g') {
-                GrnLED = !GrnLED;
-            }       
-            else if (letter == 'b') {
-                BluLED = !BluLED;
-            }       
         }
     }
 }
\ No newline at end of file