diff --git a/makeblock/src/MePS2.cpp b/makeblock/src/MePS2.cpp
index a7e8a807..d8f66694 100644
--- a/makeblock/src/MePS2.cpp
+++ b/makeblock/src/MePS2.cpp
@@ -54,7 +54,7 @@
  *   None
  */
 MePS2::MePS2() : MeSerial(0)
-{ 
+{
   _isReady = false;
   _isAvailable = false;
   _isStart = false;
@@ -69,7 +69,7 @@ MePS2::MePS2() : MeSerial(0)
  */
  MePS2::MePS2(uint8_t port) : MeSerial(port)
 {
-	_isReady = false;
+  _isReady = false;
   _isAvailable = false;
   _isStart = false;
   _lasttime = millis();
@@ -175,7 +175,7 @@ void MePS2::readSerial(void)
  *    None
  */
 boolean MePS2::readjoystick(void)
-{	
+{
   if(millis() - _lasttime > 100)
   {
     _isReady = false;
@@ -219,7 +219,7 @@ boolean MePS2::readjoystick(void)
        	return true;
       }
       else
-      {	
+      {
         _isStart = false;
         _index = 0;
         return false;
@@ -244,7 +244,7 @@ boolean MePS2::readjoystick(void)
  *    None
  */
 int MePS2::MeAnalog(uint8_t button)
-{	
+{
   if (!_isReady)
   {
     return (-999);
@@ -277,7 +277,7 @@ int MePS2::MeAnalog(uint8_t button)
  *    None
  */
 boolean MePS2::ButtonPressed(uint8_t button) 
-{	
+{
   return  ps2_data_list[button];
 }
 
@@ -298,7 +298,7 @@ boolean MePS2::ButtonPressed(uint8_t button)
 void MePS2::loop(void)
 {
   if (readjoystick() )
-  {	
+  {
     ps2_data_list[MePS2_LX] = buffer[2];
     ps2_data_list[MePS2_LY] = buffer[4];
     ps2_data_list[MePS2_RX] = buffer[6];
diff --git a/makeblock/src/MePS2.h b/makeblock/src/MePS2.h
index 60bebf59..b22813a0 100644
--- a/makeblock/src/MePS2.h
+++ b/makeblock/src/MePS2.h
@@ -53,7 +53,7 @@
 #include "MePort.h"
 #endif 
 
-#define MePS2_RX 6		
+#define MePS2_RX 6
 #define MePS2_RY 8
 #define MePS2_LX 2
 #define MePS2_LY 4
@@ -83,9 +83,9 @@
  */
 #ifndef ME_PORT_DEFINED
   class MePS2
-#else	/* !ME_PORT_DEFINED */
+#else /* !ME_PORT_DEFINED */
   class MePS2 : public MeSerial
-#endif	/* !ME_PORT_DEFINED */
+#endif  /* !ME_PORT_DEFINED */
 
 {
 public:
@@ -106,7 +106,7 @@
  *   port - RJ25 port from PORT_1 to M2
  */
   MePS2(uint8_t port);
-#else 	 // ME_PORT_DEFINED
+#else  // ME_PORT_DEFINED
 
 /**
  * Alternate Constructor which can call your own function to map the MePS2 to arduino port,
@@ -183,7 +183,7 @@
  * \par Others
  *    None
  */
-  boolean MePS2::readjoystick(void);
+  boolean readjoystick(void);
 
 /**
  * \par Function
@@ -199,7 +199,7 @@
  * \par Others
  *    None
  */
- int MePS2::MeAnalog(uint8_t button);
+  int16_t MeAnalog(uint8_t button);
 
 /**
  * \par Function
@@ -215,7 +215,7 @@
  * \par Others
  *    None
  */
-  boolean MePS2::ButtonPressed(uint8_t button);
+  boolean ButtonPressed(uint8_t button);
 
 /**
  * \par Function
@@ -232,7 +232,7 @@
  *    None
  */
   void MePS2::loop(void);
-	
+
 private:
   uint8_t _serialRead;
   uint8_t _dataLen;