This driver supports the following functions:
Special properties
Variables of the Intern driver have special properties. These properties can be accessed in the property windows und "Internal variable".
Remanence
In the properties window the remanence behavior of the variable can be defined. The property "Remanence" can have the values "Off", "Initial value" or "Remanent".
Off |
On starting the Runtime the alternate value of the variable resp. an empty string for string variables is used as the current value |
Initial value |
The current value is the value entered in the property "Initial value" |
Remanent |
The last value of the variable is used as the current value when restarting the Runtime |
On closing the Runtime the remanent values of
the variables are stored in the file
<computer_name>\<project_name>\INTERNVAR.BIN of the
project.
Effectively the values of all internal variables are saved in this
file, but only those of the remanent variables are used on a
Runtime start. If e.g. a variable is switched from "Off" resp.
"Initial value" to "Remanent", it will have the last saved value on
the next Runtime start.
Calculation Local / Network
This property defines whether the value of the variable in the Runtime comes from the local station or from the server. This property can be defined individually for each variable, even for the items of complex variables (structures).