 				if (strlen(serial_buffer) + strlen(current_buffer) < MAX_BUFFER_LENGTH) // concat only if it fits
 					strcat(current_buffer, serial_buffer);
 
+			if (current_buffer[0]) {
+				Serial.write("I ");
+				Serial.write(current_buffer);
+				Serial.write("/");
+				Serial.write(serial_buffer);
+
+				Serial.write("#");
+			}
+
 #ifdef DEBUG
 			Serial.write("initial buffer is=");
 			Serial.write(current_buffer);

						Serial.write(tmp_str);
						Serial.println();
#endif

						parse_and_execute_commands(current_buffer + i, j - i, serial_out);
						if (serial_out[0])
							Serial.write(serial_out);

void loop()
{
	char serial_out[MAX_BUFFER_LENGTH];
	serial_out[0] = 0;

	// check to see if there are new results from ultrasonic sensor
	ultrasonic_sensors_controller.update_results(serial_out);
