code: public void sendData(KNXAddress addr, Priority p, byte[] tsdu)
  		throws KNXTimeoutException, KNXLinkClosedException
  	{
  		if (detached)
  			throw new KNXIllegalStateException("TL detached");
  		tsdu[0] &= 0x03;
  		lnk.sendRequestWait(addr, p, tsdu);
  	}
docs: /* (non-Javadoc)
  @see tuwien.auto.calimero.mgmt.TransportLayer#sendData
  (tuwien.auto.calimero.KNXAddress, tuwien.auto.calimero.Priority, byte[])