Publisher Variable

Each Publisher Variable additionally has its own special properties that can be parameterized with the help of its own configuration page (see following illustration).

Publisher Variable 1:

On Change Only
If the On Change Only option is activated, the TxProcessData is only sent with the TxFrame if the value of the Publisher Variable has changed. The value in the Timeout field specifies the number of milliseconds (ms) that should elapse after a Publisher Variable was last sent before sending it again, even if the value of the Publisher Variable should not have changed in the meantime (further details in EAP send mechanism).

On Change Only

The On Change Only property cannot be used if an EL66xx is in use.

Variable Id
The Variable Id (=ProcessData ID) is the identification number of the Publisher Variable. It can be changed online with the help of a PLC program if the option Online Changeable is marked.

DataType Version
A version number can be specified here. The same version number must be configured on the subscriber side, if both version numbers are checked for equality when the variable is received (this comparison takes place by default). The version number is used to ensure that the data type of the publisher variable matches the corresponding subscriber variable. If the data type is only changed on the publisher or subscriber side, the version number must be increased to prevent the variable from being received and its values then being interpreted with the wrong data type.

Data Exchange
The rhythm with which the Publisher Variable is sent can be changed with the help of the Data Exchange property (further details in EAP send mechanism).

Data Exchange

The Data Exchange property cannot be used if an EL66xx is in use.