docs: private void doSend(byte[] msg, boolean wait, KNXAddress dst)
  		throws KNXAckTimeoutException, KNXLinkClosedException
  	{
  		if (closed)
  			throw new KNXLinkClosedException("link closed");
  		try {
  			logger.info("send message to " + dst + (wait ? ", wait for ack" : ""));
  			logger.trace("EMI " + DataUnitBuilder.toHex(msg, " "));
  			conn.send(msg, wait);
  			logger.trace("send to " + dst + " succeeded");
  		}
  		catch (final KNXPortClosedException e) {
  			logger.error("send error, closing link", e);
  			close();
  			throw new KNXLinkClosedException("link closed, " + e.getMessage());
  		}
  	}