Compatibility

The TwinCAT Database Server is a tried and tested TwinCAT product that has been around for many years. The demands on the product are constantly increasing. New developments in the TwinCAT Database Server are intended to meet these increased requirements.

The TwinCAT database connections have previously been available in versions 3.0.x, 3.1.x and 3.2.x. The current version is 3.3.x As before, the database server consists of the following components: configurator, ADS server and PLC library. Version 3.0.x includes the PLC library Tc2_Database.compiled library. The PLC library in versions 3.1.x and higher is called Tc3_Database.compiled-library.

Notes on the transition from 3.0.x to 3.1.x

In addition to new and higher-performance functions, a key aspect was compatibility between versions 3.0.x and 3.1.x. For example, old PLC code, in which the Tc2_Database.compiled library is used, can also be used with the new 3.1.x version ADS server. The old Tc2_Database.compiled library continues to be installed in version 3.1.x during setup. The XML files created by the configurator for the server differ between versions 3.0.x and 3.1.x. It is possible to read old configuration files with the new configurator (standalone) and even to convert them to the new format, if required.

Backup of the old XML configuration During an update from the TwinCAT Database Server 3.0.x to the new 3.1.x version, the old XML configuration is saved. It is renamed to "CurrentConfigDataBase_OLD.xml" and remains in the TwinCAT boot directory.

Notwithstanding the general compatibility referred to above, an old configurator and an old ADS server (version 3.0.x) cannot be used with the new Tc3_Database.compiled library. The diagram below provides a compatibility overview.

Notes on the transition from 3.1.x to 3.2.x

The file formats for the configurations are unchanged. The ADS server was merely extended with new functionalities. All other functions are still available. In version 3.2.x the old Tc2_Database.compiled-library is installed in parallel with the Tc3_Database.compiled-library during setup. The notes for the transition from 3.0.x to 3.1.x apply.

In the Tc3_Database.compiled-library, all previous function blocks have been updated from version 3.2.x onwards. The update refers to the I_TcMessage EventLogger interface. To ensure that older applications continue to function, "Evt" is appended to the names of new function blocks. All old function blocks are still contained in the library, but are now in the Obsolete folder and are marked accordingly by the compiler.

Example:

In version 3.1.x: FB_SQLCommand

In version 3.2.x: FB_SQLCommandEvt

We recommend using the function blocks with the ending "Evt" for new projects. It should be noted that the EventLogger itself is only available from TwinCAT 3.1 Build 4022.20, and therefore the function blocks can only be used from 4022.20.

Notes on the transition from 3.2.x to 3.3.x

With version 3.3.x, the modularization of the TwinCAT Database Server has been further advanced on the driver side. Full compatibility is ensured. However, some drivers are no longer automatically included in the setup and must be made available separately by the user. Example: MySQL under Windows CE. For details, please refer to the settings for the respective database in the Configuration section.