diff --git a/msg/templates/uorb/microRTPS_client.cpp.template b/msg/templates/uorb/microRTPS_client.cpp.template
index ad902cfa5b..01bd53ae7a 100644
--- a/msg/templates/uorb/microRTPS_client.cpp.template
+++ b/msg/templates/uorb/microRTPS_client.cpp.template
@@ -206,8 +206,8 @@ void* send(void*)
     struct timespec end;
     clock_gettime(0, &end);
     double elapsed_secs = double(end.tv_sec - begin.tv_sec) + double(end.tv_nsec - begin.tv_nsec)/double(1000000000);
-    printf("\nSENT:     %lu messages in %d LOOPS, %llu bytes in %.03f seconds - %.02fKB/s\n",
-            (unsigned long)sent, loop, total_sent, elapsed_secs, (double)total_sent/(1000*elapsed_secs));
+    printf("\nSENT:     %lu messages in %d LOOPS, %lu bytes in %.03f seconds - %.02fKB/s\n",
+            sent, loop, total_sent, elapsed_secs, (double)total_sent/(1000*elapsed_secs));
 
     return nullptr;
 }
@@ -271,7 +271,7 @@ static int micrortps_start(int argc, char *argv[])
 
     char data_buffer[BUFFER_SIZE] = {};
     int read = 0;
-    char topic_ID = 255;
+    uint8_t topic_ID = 255;
 
     // Declare received topics
 @[for topic in recv_topics]@
diff --git a/msg/templates/urtps/microRTPS_agent.cxx.template b/msg/templates/urtps/microRTPS_agent.cxx.template
index 80e3a43a85..8f0712339f 100644
--- a/msg/templates/urtps/microRTPS_agent.cxx.template
+++ b/msg/templates/urtps/microRTPS_agent.cxx.template
@@ -159,7 +159,7 @@ void t_send(void *data)
 {
     char data_buffer[BUFFER_SIZE] = {};
     int length = 0;
-    char topic_ID = 255;
+    uint8_t topic_ID = 255;
 
     while (running)
     {