BECKHOFF EL6930 - Manual (Page 42)

Operation
40 EL6930
4.2.11 Communication between TwinCAT controllers
The MASTER_MESSAGE and SLAVE_MESSAGE data types are used for communication between two
or more TwinCAT controllers via network variables.
Associated variables have to be created under Publisher and Subscriber on the communicating
controllers.
During TwinSAFE communication one side acts as the master, the other one as the slave.
This results in the following data types:
TwinSAFE Master Publisher MASTER_MESSAGE
TwinSAFE Master Subscriber SLAVE_MESSAGE
TwinSAFE Slave Publisher SLAVE_MESSAGE
TwinSAFE Slave Subscriber MASTER_MESSAGE
The link with the via TwinSAFE logic terminal EL6930 is established with the following dialog:
The connection created must now be made known to the TwinSAFE logic terminal. This is done by
marking the TwinSAFE connection list and pressing the right mouse button.
Create a new connection in the list of connections and create associated variables of the required type