Rockwell Automation 1753-PCS-PAR Using RSLogix Guard PLUS! with GuardPLC Controllers - Manual (Page 45)

Publication 1753-PM001A-EN-P - November 2005
Create a GuardPLC Project 3-5
Understand the Signal Editor
The Signal Editor lets you define the signals for your application.
The Name column contains a unique name for the signal. The Name is
required and must be less than 32 characters in length.
The Type column indicates the desired data type for the signal. The
default is Boolean.
Signals are typically stored in RAM memory. However, a checkmark in
the Retain column specifies that the signal be stored in Flash memory,
thus retaining its value following a restart caused by a power cycle or
a STOP to RUN mode transition.
The Constant column specifies that the value of the signal cannot be
changed in program code. It will always equal the value entered in
the Init Value column.
The Init Value column specifies the initial value of the signal. This
value can be changed by program code if Constant is not checked.
IMPORTANT
Even if a signal is marked as Retain, specific program
code is required to prevent it from being overwritten.
In addition, the Retain feature requires a warmstart,
either by choosing Warmstart from the Resource menu
of the Control Panel or by right-clicking on the Type
Instance of the Resource in the project tree and
choosing Properties. Then, choose Warmstart from the
Autostart Enable pull-down menu.