03_07_02 Datapoint Types v01.08.03 AS.pdf (or later version). This information is collectively referred to as the KNX Data Definitions or KNX Data Defs.
The KNX Data Defs are stored in a file called knx_extra.xml. In addition, there is information about the units, minimum and
maximum values, and compatible Control Point types for each of the KNX Datapoint Types
The knx_extra.xml file works along similar lines to KNX’s knx_master.xml file, which is part of the ETS installation and is updated from time to time with new KNX Datapoint Types by the KNX organization.
The knx_extra.xml file is fundamental to the correct operation of the KNXnet/IP driver and it is internally signed to avoid the possibility
of introducing erroneous operation of the KNXnet/IP driver.
Each release of the KNXnet/IP driver contains a version of knx_extra.xml that is current at the time of release, however newer versions of the knx_extra.xml file will be published to keep pace with changes to the KNX knx_master.xml.
027) and the version number of the KNXnet/IP driver module (for example 3.8.41.1.0.29).