diff --git a/examples/arduino/EspLinkSample/EspLinkSample.ino b/examples/arduino/EspLinkSample/EspLinkSample.ino
index c776994..9f443bf 100644
--- a/examples/arduino/EspLinkSample/EspLinkSample.ino
+++ b/examples/arduino/EspLinkSample/EspLinkSample.ino
@@ -1,16 +1,6 @@
 
 #include "WebServer.h"
-
-#define LED_PIN  13
-
-int8_t  blinking = 0;
-int8_t  frequency = 10;
-uint8_t pattern = 2;
-uint16_t elapse = 100;
-uint16_t elapse_delta = 200;
-uint32_t next_ts = 0;
-
-void ledHtmlCallback(WebServerCommand command, char * data, int dataLen);
+#include "Pages.h"
 
 const char ledURL[] PROGMEM = "/LED.html.json";
 
@@ -26,96 +16,13 @@ void setup()
   Serial.begin(57600);
   webServer.init();
 
-  pinMode(LED_PIN, OUTPUT);
-  digitalWrite(LED_PIN, false);
+  ledInit();
 }
 
 void loop()
 {
   webServer.loop();
-  
-  if( blinking )
-  {
-    if( next_ts <= millis() )
-    {
-      digitalWrite(LED_PIN, !digitalRead(LED_PIN));
-      next_ts += elapse;
-      elapse = elapse_delta - elapse;
-    }
-  }
-}
-
 
-void ledHtmlCallback(WebServerCommand command, char * data, int dataLen)
-{
-  switch(command)
-  {
-    case BUTTON_PRESS:
-      if( strcmp_P(data, PSTR("btn_on") ) == 0 )
-      {
-        blinking = 0;
-        digitalWrite(LED_PIN, true);
-      } else if( strcmp_P(data, PSTR("btn_off") ) == 0 )
-      {
-        blinking = 0;
-        digitalWrite(LED_PIN, false);
-      } else if( strcmp_P(data, PSTR("btn_blink") ) == 0 )
-      {
-        blinking = 1;
-        next_ts = millis() + elapse;
-      }
-      break;
-    case SET_FIELD:
-      if( strcmp_P(data, PSTR("frequency") ) == 0 )
-      {
-        frequency = webServer.getArgInt();
-        digitalWrite(LED_PIN, false);
-        elapse_delta = 2000 / frequency;
-        elapse = pattern * elapse_delta / 4;
-      }
-      else if( strcmp_P(data, PSTR("pattern") ) == 0 )
-      {
-        char * arg = webServer.getArgString();
-
-        if( strcmp_P(arg, PSTR("25_75")) == 0 )
-          pattern = 1;
-        else if( strcmp_P(arg, PSTR("50_50")) == 0 )
-          pattern = 2;
-        else if( strcmp_P(arg, PSTR("75_25")) == 0 )
-          pattern = 3;
-
-        digitalWrite(LED_PIN, false);
-        elapse = pattern * elapse_delta / 4;
-      }
-      break;
-    case LOAD:
-      webServer.setArgNum(3);
-      webServer.setArgInt("frequency", frequency);
-
-      switch(pattern)
-      {
-        case 1:
-          webServer.setArgStringP("pattern", PSTR("25_75"));
-          break;
-        case 2:
-          webServer.setArgStringP("pattern", PSTR("50_50"));
-          break;
-        case 3:
-          webServer.setArgStringP("pattern", PSTR("75_25"));
-          break;
-      }
-    case REFRESH:
-      if( command == REFRESH )
-        webServer.setArgNum(1);
-
-      if( blinking )
-        webServer.setArgStringP("text", PSTR("LED is blinking"));
-      else
-        webServer.setArgStringP("text", digitalRead(LED_PIN) ? PSTR("LED is turned on") : PSTR("LED is turned off"));
-      break;
-    default:
-      break;
-  }
+  ledLoop();
 }
 
-
diff --git a/examples/arduino/EspLinkSample/LedPage.ino b/examples/arduino/EspLinkSample/LedPage.ino
new file mode 100644
index 0000000..768520b
--- /dev/null
+++ b/examples/arduino/EspLinkSample/LedPage.ino
@@ -0,0 +1,192 @@
+#include "WebServer.h"
+
+#define LED_PIN  13
+
+int8_t  blinking = 0;
+int8_t  frequency = 10;
+uint8_t pattern = 2;
+uint16_t elapse = 100;
+uint16_t elapse_delta = 200;
+uint32_t next_ts = 0;
+
+#define MAX_LOGS 5
+uint32_t log_ts[MAX_LOGS];
+uint8_t  log_msg[MAX_LOGS];
+uint8_t  log_ptr = 0;
+
+void ledInit()
+{
+  pinMode(LED_PIN, OUTPUT);
+  digitalWrite(LED_PIN, false);
+}
+
+void ledLoop()
+{ 
+  if( blinking )
+  {
+    if( next_ts <= millis() )
+    {
+      digitalWrite(LED_PIN, !digitalRead(LED_PIN));
+      next_ts += elapse;
+      elapse = elapse_delta - elapse;
+    }
+  }
+}
+
+void ledAddLog(uint8_t msg)
+{
+  if( log_ptr >= MAX_LOGS )
+    log_ptr = MAX_LOGS - 1;
+
+  for(int8_t i=log_ptr-1; i >= 0; i--)
+  {
+    log_ts[i+1] = log_ts[i];
+    log_msg[i+1] = log_msg[i];
+  }
+  log_msg[0] = msg;
+  log_ts[0] = millis();
+  log_ptr++;
+}
+
+void ledHistoryToLog(char * buf)
+{
+  buf[0] = 0;
+  strcat(buf, "[");
+  for(uint8_t i=0; i < log_ptr; i++)
+  {
+    if( i != 0 )
+      strcat(buf, ",");
+    
+    char bf[20];
+    sprintf(bf, "\"%lds: ", log_ts[i] / 1000);
+    strcat(buf, bf);
+
+    uint8_t msg = log_msg[i];
+    if( msg == 0xE1 )
+    {
+      strcat_P(buf, PSTR("set pattern to 25%-75%"));
+    }
+    else if( msg == 0xE2 )
+    {
+      strcat_P(buf, PSTR("set pattern to 50%-50%"));
+    }
+    else if( msg == 0xE3 )
+    {
+      strcat_P(buf, PSTR("set pattern to 75%-25%"));
+    }
+    else if( msg == 0xF0 )
+    {
+      strcat_P(buf, PSTR("set led on"));
+    }
+    else if( msg == 0xF1 )
+    {
+      strcat_P(buf, PSTR("set led blinking"));
+    }
+    else if( msg == 0xF2 )
+    {
+      strcat_P(buf, PSTR("set led off"));
+    }
+    else
+    {
+      strcat_P(buf, PSTR("set frequency to "));
+      sprintf(bf, "%d Hz", msg);
+      strcat(buf, bf);
+    }
+    strcat(buf, "\"");
+  }
+  strcat(buf, "]");
+}
+
+
+void ledHtmlCallback(WebServerCommand command, char * data, int dataLen)
+{
+  switch(command)
+  {
+    case BUTTON_PRESS:
+      if( strcmp_P(data, PSTR("btn_on") ) == 0 )
+      {
+        if( blinking || digitalRead(LED_PIN) == false )
+          ledAddLog(0xF0);
+        blinking = 0;
+        digitalWrite(LED_PIN, true);
+      } else if( strcmp_P(data, PSTR("btn_off") ) == 0 )
+      {
+        if( blinking || digitalRead(LED_PIN) == true )
+          ledAddLog(0xF2);
+        blinking = 0;
+        digitalWrite(LED_PIN, false);
+      } else if( strcmp_P(data, PSTR("btn_blink") ) == 0 )
+      {
+        if( !blinking )
+          ledAddLog(0xF1);
+        blinking = 1;
+        next_ts = millis() + elapse;
+      }
+      break;
+    case SET_FIELD:
+      if( strcmp_P(data, PSTR("frequency") ) == 0 )
+      {
+        int8_t oldf = frequency;
+        frequency = webServer.getArgInt();
+        digitalWrite(LED_PIN, false);
+        elapse_delta = 2000 / frequency;
+        elapse = pattern * elapse_delta / 4;
+        if( oldf != frequency )
+          ledAddLog(frequency);
+      }
+      else if( strcmp_P(data, PSTR("pattern") ) == 0 )
+      {
+        int8_t oldp = pattern;
+        char * arg = webServer.getArgString();
+
+        if( strcmp_P(arg, PSTR("25_75")) == 0 )
+          pattern = 1;
+        else if( strcmp_P(arg, PSTR("50_50")) == 0 )
+          pattern = 2;
+        else if( strcmp_P(arg, PSTR("75_25")) == 0 )
+          pattern = 3;
+
+        digitalWrite(LED_PIN, false);
+        elapse = pattern * elapse_delta / 4;
+
+        if( oldp != pattern )
+          ledAddLog(0xE0 + pattern);
+      }
+      break;
+    case LOAD:
+      webServer.setArgNum(4);
+      webServer.setArgInt("frequency", frequency);
+
+      switch(pattern)
+      {
+        case 1:
+          webServer.setArgStringP("pattern", PSTR("25_75"));
+          break;
+        case 2:
+          webServer.setArgStringP("pattern", PSTR("50_50"));
+          break;
+        case 3:
+          webServer.setArgStringP("pattern", PSTR("75_25"));
+          break;
+      }
+    case REFRESH:
+      {
+        if( command == REFRESH )
+          webServer.setArgNum(2);
+
+        if( blinking )
+          webServer.setArgStringP("text", PSTR("LED is blinking"));
+        else
+          webServer.setArgStringP("text", digitalRead(LED_PIN) ? PSTR("LED is turned on") : PSTR("LED is turned off"));
+
+        char buf[255];
+        ledHistoryToLog(buf);
+        webServer.setArgJson("led_history", buf);
+      }
+      break;
+    default:
+      break;
+  }
+}
+
+
diff --git a/examples/arduino/EspLinkSample/Pages.h b/examples/arduino/EspLinkSample/Pages.h
new file mode 100644
index 0000000..efa277c
--- /dev/null
+++ b/examples/arduino/EspLinkSample/Pages.h
@@ -0,0 +1,10 @@
+#ifndef PAGES_H
+#define PAGES_H
+
+void ledHtmlCallback(WebServerCommand command, char * data, int dataLen);
+void ledLoop();
+void ledInit();
+
+#endif /* PAGES_H */
+
+
diff --git a/examples/arduino/EspLinkSample/WebServer.cpp b/examples/arduino/EspLinkSample/WebServer.cpp
index 7aab354..a72faa0 100644
--- a/examples/arduino/EspLinkSample/WebServer.cpp
+++ b/examples/arduino/EspLinkSample/WebServer.cpp
@@ -162,6 +162,22 @@ void WebServer::setArgStringP(const char * name, const char * value)
   args_to_send--;
 }
 
+void WebServer::setArgJson(const char * name, const char * value)
+{
+  if( args_to_send <= 0 )
+    return;
+    
+  uint8_t nlen = strlen(name);
+  uint8_t vlen = strlen(value);
+  char buf[nlen + vlen + 3];
+  buf[0] = WEB_JSON;
+  strcpy(buf+1, name);
+  strcpy(buf+2+nlen, value);
+  espLink.sendPacketArg(nlen+vlen+2, (uint8_t *)buf);
+  
+  args_to_send--;
+}
+
 void WebServer::setArgInt(const char * name, int32_t value)
 {
   if( args_to_send <= 0 )
diff --git a/examples/arduino/EspLinkSample/WebServer.h b/examples/arduino/EspLinkSample/WebServer.h
index 28365be..e1742b6 100644
--- a/examples/arduino/EspLinkSample/WebServer.h
+++ b/examples/arduino/EspLinkSample/WebServer.h
@@ -73,6 +73,7 @@ class WebServer
 
     void               setArgNum(uint8_t num);
     void               setArgInt(const char * name, int32_t value);
+    void               setArgJson(const char * name, const char * value);
     void               setArgString(const char * name, const char * value);
     void               setArgStringP(const char * name, const char * value);