diff --git a/html_src/gulpfile.js b/html_src/gulpfile.js
index 41969bf..ee98a02 100644
--- a/html_src/gulpfile.js
+++ b/html_src/gulpfile.js
@@ -33,5 +33,6 @@ elixir(function (mix) {
 		'js-src/page_waveform.js',
 		'js-src/page_spectrogram.js',
 		'js-src/page_status.js',
+		'js-src/page_mon.js',
 	], 'js/all.js');
 });
diff --git a/html_src/js-src/page_mon.js b/html_src/js-src/page_mon.js
index 7ee3f1c..ec57d6b 100644
--- a/html_src/js-src/page_mon.js
+++ b/html_src/js-src/page_mon.js
@@ -1,6 +1,14 @@
 var page_mon = (function() {
 	var mon = {};
 
+	mon.captureRef = function() {
+		// TODO ajax & update the field
+	};
+
+	mon.compareNow = function() {
+		// TODO ajax & show result
+	};
+
 	mon.init = function() {
 		//
 	};
diff --git a/html_src/page_monitoring.php b/html_src/page_monitoring.php
index 21adee8..2b5a517 100644
--- a/html_src/page_monitoring.php
+++ b/html_src/page_monitoring.php
@@ -16,7 +16,7 @@
 			<th>Actual&nbsp;distance:</th>
 			<td>
 				<span id="reporting" class="Valfield">N/A</span>
-				<a onclick="page_mon.toggleReporting()" class="button btn-blue">Measure</a>
+				<a onclick="page_mon.compareNow()" class="button btn-blue">Measure</a>
 			</td>
 		</tr>
 	</table>