Superglobal Variables

The interface Superglobal Variables communicates with other projects on the same server or the same server network.

Functionality

Variables are created in the Installation according to data type. Each variable can be read and written by all participating projects. Every value is stored persistently to retain the data after a server restart.

Note: The value NULL cannot be written.

When multiple servers are synchronized, each server must have an assigned gateway.

Monitor

The monitor displays all transmissions of a value. The value age is hidden and can be determined by the timestamp in the monitor.

The source always shows the project that sent the value.

Data Types

The data types are identical to those of the PLC. However, they are only encoded when sending and receiving. This means a boolean value can also be transmitted via an String variable. Decoding on the other side may lead to unintended conversion of the value when received.

Variable	Description
value	Value to be transmitted.
age	Last known transmission as timestamp.