docs: public static Datapoint create(XMLReader r) throws KNXMLException
  	{
  		if (r.getPosition() != XMLReader.START_TAG)
  			r.read();
  		if (r.getPosition() == XMLReader.START_TAG) {
  			if (readDPType(r))
  				return new StateDP(r);
  			return new CommandDP(r);
  		}
  		throw new KNXMLException("no KNX datapoint", null, r.getLineNumber());
  	}