diff --git a/shonai_tiiki_map_tansaku.html b/shonai_tiiki_map_tansaku.html
index a68c57c..5032eac 100644
--- a/shonai_tiiki_map_tansaku.html
+++ b/shonai_tiiki_map_tansaku.html
@@ -45,6 +45,7 @@
 <p>
   <button id="start" type="button">START</button>
   <button id="stop" type="button">STOP</button>
+  <button id="reset" type="button">reset</button>
 </p>
  
 <p>