Made song editable

Based on pull request #1...
The list of frequencies to be played has been moved from the JS to a textbox in the HTML.
Editing the content of the box will change what gets played.
The format also is more human human readable and consistent with the songfile from #1.
If you copy and paste the smb.song file, it should work.

Author: rocketinventor

In Javascript/airgap.html

@@ -16,8 +16,35 @@
 	<div class="content">
 		</br>
 		<input type="button" value="Play Song" onclick="start()"></br></br>
-		<textarea id="logs" style="width:70%;min-height:300px">Tested with Chrome at 1560Khz
-		</textarea>
+		<textarea id="logs" style="width:70%;min-height:100px">Tested with Chrome at 1560Khz</textarea>
+		<textarea id="tones" style="width:70%;min-height:200px">
+Feel free to edit the code below. Just make sure you keep to the format that it's in and have all of the punctuation.
+:beep frequency=2673 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2093 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2673 length=400;
+:beep frequency=2673 length=400;
+:beep frequency=2673 length=790;
+:beep frequency=2349 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2349 length=790;
+:beep frequency=2673 length=400;
+:beep frequency=3136 length=400;
+:beep frequency=3136 length=790;
+:beep frequency=2673 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2093 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2673 length=400;
+:beep frequency=2673 length=400;
+:beep frequency=2673 length=400;
+:beep frequency=2673 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2673 length=400;
+:beep frequency=2349 length=400;
+:beep frequency=2093 length=790;</textarea>
 		<div style="font-size:14px">Ported by Yeo Quan Yang. Credits to the original author William Entriken @https://github.com/fulldecent</div><br/>
 		<div style="font-size:14px">Project site at <a href="https://github.com/fulldecent/system-bus-radio">https://github.com/fulldecent/system-bus-radio</a></div><br/>
 		<div style="font-size:14px">List of computers that work and what frequency to try at <a href="https://github.com/fulldecent/system-bus-radio/blob/master/TEST-DATA.tsv">https://github.com/fulldecent/system-bus-radio/blob/master/TEST-DATA.tsv</a></div>

In Javascript/airgap.js

@@ -29,30 +29,22 @@ function square_am_signal(time,freq) {
 }
 
 function start() {
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.400, 2093);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.790, 2673);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.790, 2349);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 3136);
-    square_am_signal(0.790, 3136);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.400, 2093);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.400, 2673);
-    square_am_signal(0.400, 2349);
-    square_am_signal(0.790, 2093);
+	var song = document.getElementById("tones").value.split(":");
+	var length = song.length;
+	var i = 1, line, time, freq;
+	while (1 <= length) {
+		line = song[i].split(" ");
+		if (line[0] == "beep") {
+			freq = +line[0].split("=")[1];
+			time = +line[2].split("=")[1].slice(0,-1);
+			square_am_signal(time, freq);
+		}
+		if (line[0] == "delay") {
+			// delay
+		}
+		if (song[i] == "end") {
+			i = 1;
+		}
+		i++;
+	}
 }