Sub: turn counter improvements

ArduSub/turn_counter.cpp

@@ -55,8 +55,11 @@ void Sub::update_turn_counter()
 		break;
 	}
 	static int32_t last_turn_count_printed;
-	if ( quarter_turn_count/4 != last_turn_count_printed ) {
-		gcs_send_text_fmt(MAV_SEVERITY_INFO,"Tether is turned %i turns %s",int32_t(quarter_turn_count/4),(quarter_turn_count>0)?"to the right":"to the left");
+	static uint32_t last_turn_announce_ms = 0;
+	uint32_t tnow = AP_HAL::millis();
+	if ( quarter_turn_count/4 != last_turn_count_printed  && tnow > last_turn_announce_ms + 2000) {
+		last_turn_announce_ms = tnow;
+		gcs_send_text_fmt(MAV_SEVERITY_INFO,"Tether is turned %i turns %s",int32_t(abs(quarter_turn_count)/4),(quarter_turn_count>0)?"to the right":"to the left");
 		last_turn_count_printed = quarter_turn_count/4;
 	}
 	last_turn_state = turn_state;