Added comments to code

src/sketch.ino

@@ -9,21 +9,60 @@
 
 void setup()
 {
-  // initialize serial comms
-  Serial.begin(9600); 
+    // Communication with the computer is not needed in this project.
+    //Serial.begin(9600); 
+    // Set digital pins as inputs ready to read incoming data from buttons.
+    for(int i = 5; i < 13; ++i) {
+        pinMode(i, INPUT);
+    }
 }
 
+// Define integer frequencies in hertz from A (440hz) chromatically.
+int notes[8] = {440, 466, 493, 523, 554, 587, 622, 659};
+// Define a a global variable for pitch.
+int pitch;
+
 void loop()
 {
-  // read A0
-  int val1 = analogRead(0);
-  // read A1
-  int val2 = analogRead(1);
-  // print to serial
-  Serial.print(val1);
-  Serial.print(" ");
-  Serial.print(val2);
-  Serial.print("\n");
-  // wait 
-  delay(50);
+    // Declare a bool for testing if button is active.
+    bool active = false;
+
+    // For each button index, check if button is currently pressed...
+    int j = 0;
+    for(int i = 5; i < 13; ++i) {
+        active = digitalRead(i);
+        // If it is, set the output pitch to the frequency stored in the notes
+        // variable at the index of the button pressed
+        if(active) {
+            pitch = notes[j];
+            // break out of for loop as further iterations are not neccesary.
+            break;
+        }
+        // If note isn't active then increment index counter.
+        ++j;
+    }
+    // If no note is active then silence instrument.
+    if(!active) {
+        noTone(13);
+    }
+    // Otherwise, output a tone.
+    else {
+        tone(13,pitch,20);
+    }
+    
+    // Disable FSR for now...
+    /*
+    int sensorVal = analogRead(0);
+
+    // Scale value read from between the known minimum and maximum values of
+    // the sensor, to a desired range (in Hz)
+    pitch = map(sensorVal, 0, 1023, 0, 2000);
+
+
+    // Output a tone, via digital output 13, to the speaker.
+    // The 3rd arguments represents the duration of the tone in milliseconds.
+
+    // Pause for 50 milliseconds
+    delay(50);
+    */
 }