diff --git a/src/MindVisionMain.cpp b/src/MindVisionMain.cpp
index 1250ebc..3e96743 100644
--- a/src/MindVisionMain.cpp
+++ b/src/MindVisionMain.cpp
@@ -4,6 +4,7 @@
 #include <chrono>
 #include <thread>
 #include <memory>
+#include <unistd.h>
 
 #include <opencv2/opencv.hpp>
 
@@ -25,7 +26,7 @@ void output_control_data(const cv::Point2f* ballistic_point,
                         bool use_ttl) {
     // Only send data when TTL is enabled, meets frame interval, and has valid target
     if (use_ttl && frame_counter % 5 == 0 && ballistic_point != nullptr) {
-        std::string send_str;
+        std::ostringstream send_str;
 
         // Calculate offset (based on actual image center)
         int ballistic_offset_x = static_cast<int>(ballistic_point->x - img_center.x);
@@ -37,11 +38,14 @@ void output_control_data(const cv::Point2f* ballistic_point,
         else if (target_color == "blue") simplified_color = "b";
 
         // Construct send string
-        send_str = "s " + simplified_color + " " + std::to_string(ballistic_offset_x) + " " + std::to_string(ballistic_offset_y);
+        send_str << "s " << simplified_color << " " << std::to_string(ballistic_offset_x) << " " << std::to_string(ballistic_offset_y) << "\n";
 
         // Send data
         if (ttl_communicator != nullptr) {
-            ttl_communicator->send_data(send_str);
+            ttl_communicator->send_data(send_str.str());
+
+        }else{
+            std::cerr << "Error: TTLCommunicator is a null pointer!" << std::endl;
         }
     }
 }
diff --git a/src/TTLCommunicator.cpp b/src/TTLCommunicator.cpp
index cc0e9da..f0bdd19 100644
--- a/src/TTLCommunicator.cpp
+++ b/src/TTLCommunicator.cpp
@@ -52,7 +52,7 @@ bool TTLCommunicator::send_data(const std::string& data) {
             std::cerr << "Error writing to serial port: " << strerror(errno) << std::endl;
             return false;
         } else {
-            std::cout << "Sent " << bytes_written << " bytes: " << data << std::endl;
+            std::cout << "Sent " << bytes_written << " bytes: " << data;
             fsync(serial_fd); // Ensure data is sent
             return true;
         }