some reaction wheel fixes

mission/devices/RwHandler.h

@@ -46,6 +46,8 @@ public:
     static const ReturnValue_t MISSING_END_SIGN = MAKE_RETURN_CODE(0xB4);
     //! [EXPORT] : [COMMENT] Reaction wheel only responds with empty frames.
     static const ReturnValue_t NO_REPLY = MAKE_RETURN_CODE(0xB5);
+    //! [EXPORT] : [COMMENT] Expected a start marker as first byte
+    static const ReturnValue_t NO_START_MARKER = MAKE_RETURN_CODE(0xB6);
 
 protected:
 	void doStartUp() override;