diff --git a/src/test_topic/CMakeLists.txt b/src/test_topic/CMakeLists.txt
index fdcb976..11f9219 100644
--- a/src/test_topic/CMakeLists.txt
+++ b/src/test_topic/CMakeLists.txt
@@ -9,8 +9,10 @@ project(test_topic)
 ## is used, also find other catkin packages
 find_package(catkin REQUIRED COMPONENTS
   roscpp
+  rospy
   std_msgs
   std_srvs
+  message_generation
 )
 
 ## System dependencies are found with CMake's conventions
@@ -47,11 +49,10 @@ find_package(catkin REQUIRED COMPONENTS
 ##   * add every package in MSG_DEP_SET to generate_messages(DEPENDENCIES ...)
 
 ## Generate messages in the 'msg' folder
-# add_message_files(
-#   FILES
-#   Message1.msg
-#   Message2.msg
-# )
+add_message_files(
+  FILES 
+  Bytes.msg
+)
 
 ## Generate services in the 'srv' folder
 # add_service_files(
@@ -68,10 +69,10 @@ find_package(catkin REQUIRED COMPONENTS
 # )
 
 ## Generate added messages and services with any dependencies listed here
-# generate_messages(
-#   DEPENDENCIES
-#   std_msgs
-# )
+generate_messages(
+  DEPENDENCIES
+  std_msgs
+)
 
 ################################################
 ## Declare ROS dynamic reconfigure parameters ##
@@ -103,9 +104,9 @@ find_package(catkin REQUIRED COMPONENTS
 ## CATKIN_DEPENDS: catkin_packages dependent projects also need
 ## DEPENDS: system dependencies of this project that dependent projects also need
 catkin_package(
-#  INCLUDE_DIRS include
+  INCLUDE_DIRS include
 #  LIBRARIES test_topic
-#  CATKIN_DEPENDS roscpp std_msgs
+  CATKIN_DEPENDS roscpp rospy message_runtime
 #  DEPENDS system_lib
 )
 
diff --git a/src/test_topic/include/test_topic/minHandler.h b/src/test_topic/include/test_topic/minHandler.h
index 3d11cca..884ee9a 100644
--- a/src/test_topic/include/test_topic/minHandler.h
+++ b/src/test_topic/include/test_topic/minHandler.h
@@ -13,15 +13,15 @@
  */
 
 #include <ros/ros.h>
-#include <std_msgs/String.h>
 #include <std_srvs/Empty.h>
 #include <vector>
 #include <thread>
+#include "test_topic/Bytes.h"
 
 namespace xyfc_std
 {
 
-using MsgType = std_msgs::String;
+using MsgType = test_topic::Bytes;
 using ThreadFuncType = boost::function<void (void)>;
 
 /**
diff --git a/src/test_topic/msg/Bytes.msg b/src/test_topic/msg/Bytes.msg
new file mode 100644
index 0000000..236ddc5
--- /dev/null
+++ b/src/test_topic/msg/Bytes.msg
@@ -0,0 +1,4 @@
+uint8[] data
+time tick
+int64 length
+int64 id
diff --git a/src/test_topic/package.xml b/src/test_topic/package.xml
index 63a5dbe..e00c5c7 100644
--- a/src/test_topic/package.xml
+++ b/src/test_topic/package.xml
@@ -50,14 +50,26 @@
   <!--   <doc_depend>doxygen</doc_depend> -->
   <buildtool_depend>catkin</buildtool_depend>
   <build_depend>roscpp</build_depend>
+  <build_depend>rospy</build_depend>
   <build_depend>std_msgs</build_depend>
   <build_depend>std_srvs</build_depend>
   <build_export_depend>roscpp</build_export_depend>
+  <build_export_depend>rospy</build_export_depend>
   <build_export_depend>std_msgs</build_export_depend>
   <exec_depend>roscpp</exec_depend>
+  <exec_depend>rospy</exec_depend>
   <exec_depend>std_msgs</exec_depend>
   <exec_depend>std_srvs</exec_depend>
 
+  <build_depend>message_generation</build_depend>
+  <build_depend>message_runtime</build_depend>
+ 
+  <build_export_depend>message_generation</build_export_depend>
+  <build_export_depend>message_runtime</build_export_depend>
+ 
+  <exec_depend>message_generation</exec_depend>
+  <exec_depend>message_runtime</exec_depend>
+
 
   <!-- The export tag contains other, unspecified, tags -->
   <export>
diff --git a/src/test_topic/src/minSubscriber.cpp b/src/test_topic/src/minSubscriber.cpp
index 551714a..f86b538 100644
--- a/src/test_topic/src/minSubscriber.cpp
+++ b/src/test_topic/src/minSubscriber.cpp
@@ -32,8 +32,9 @@ MinSubscriber::~MinSubscriber()
 
 void MinSubscriber::callback(const boost::shared_ptr<MsgType const> &msg)
 {
-    ROS_INFO("I heard: [%s]", msg->data.c_str());
-    _serial.send(msg->data.c_str(), strlen(msg->data.c_str()));
+    ROS_INFO("I heard: [%s]", &msg->data[0]);
+
+    _serial.send((const char *)&msg->data[0], msg->length);
 }
 
 int main(int argc, char *argv[])
diff --git a/src/test_topic/src/testMinHandler.cpp b/src/test_topic/src/testMinHandler.cpp
index 2ce8679..76063a5 100644
--- a/src/test_topic/src/testMinHandler.cpp
+++ b/src/test_topic/src/testMinHandler.cpp
@@ -17,14 +17,13 @@ protected:
 
 void testMinHandler::callback(const boost::shared_ptr<MsgType const> &msg)
 {
-    std::stringstream ss;
-
-    ss << "handled data: " << msg->data;
-    ROS_INFO("handle :%s", msg->data.c_str());
+    ROS_INFO("handle :%s", &msg->data[0]);
     std::this_thread::sleep_for(std::chrono::seconds(2));
+    std::string str = "handled :";
+    str.append((const char *)&msg->data[0]);
 
     MsgType send;
-    send.data = ss.str();
+    send.data.assign(str.begin(), str.end());
     _pub.publish(send);
 }
 
diff --git a/src/test_topic/src/timerPublisher.cpp b/src/test_topic/src/timerPublisher.cpp
index 31c4f03..e0b6bd8 100644
--- a/src/test_topic/src/timerPublisher.cpp
+++ b/src/test_topic/src/timerPublisher.cpp
@@ -1,7 +1,7 @@
 #include <ros/ros.h>
-#include <std_msgs/String.h>
+#include "test_topic/Bytes.h"
 
-using MsgType = std_msgs::String;
+using MsgType = test_topic::Bytes;
 class TimerPublisher: ros::NodeHandle {
 public:
     TimerPublisher();
@@ -29,13 +29,19 @@ void TimerPublisher::run()
     ros::Rate loop_rate(10);
     while (ros::ok())
     {
-        std_msgs::String msg;
+        test_topic::Bytes msg;
 
         std::stringstream ss;
         ss << "hello world " << _count++ << "\n";
-        msg.data = ss.str();
+        auto str = ss.str();
 
-        ROS_INFO("%s", msg.data.c_str());
+        msg.data.assign(str.begin(), str.end());
+        msg.data.push_back(0);
+        msg.id = 1,
+        msg.length = str.size() + 1;
+        msg.tick = ros::Time::now();
+
+        ROS_INFO("%s", str.c_str());
         _sender.publish(msg);
 
         ros::spinOnce();