Editing Remanent Global Variables Lists

If they are supported by the runtime system, remanent variables may be processed. There are two types of remanent global variables:

• Retain variables remain unchanged after an uncontrolled shutdown of the runtime system (off/on) or an ‘Online’ ‘Reset’.
• Persistent variables remain only unchanged after a program ‘Online’ ‘Download’.

Persistent variables are not automatically also Retain variables !

Remanent variables are additionally assigned the keyword RETAIN and/or PERSISTENT.

Syntax:

VAR_GLOBAL RETAIN

(* Variables declarations *)

END_VAR

VAR_GLOBAL PERSISTENT

(* Variables declarations *)

END_VAR

For the combination of retain and persistent properties both keywords are used:

VAR_GLOBAL RETAIN PERSISTENT or VAR_GLOBAL PERSISTENT RETAIN