diff --git a/cubesatsim/play_pwm.cpp b/cubesatsim/play_pwm.cpp
index 6416c54b..c32c854c 100644
--- a/cubesatsim/play_pwm.cpp
+++ b/cubesatsim/play_pwm.cpp
@@ -387,7 +387,8 @@ int led_pin = LED_BUILTIN;
 //       buffer2[index1++] = octet;
          i.write(&octet, 1);
          index1++;
-       
+         Serial.write(octet);	// print octet from Serial2
+	     
        if (octet == end_flag[flag_count]) {  // looking for end flag
 //         if (end_flag_detected) {
             flag_count++;