HIMA HIQuad H41X, Системное руководство

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System Programming
HI 803 211 E Rev. 1.01.00 Page 67 of 110
6 Programming
SILworX is installed on a personal computer (PC) and activated through a license. To create the
user program and configure a resource, SILworX does not have to be connected to the HIQuad
system. To perform loading, testing and monitoring tasks, the PC is connected to the HIQuad X
system via an Ethernet interface.
6.1 Using Variables in a Project
A variable is a placeholder for a value within the program logic. The variable name is used to
symbolically address the storage space containing the stored value.
Two essential advantages result from using symbolic names instead of physical addresses:

The names of inputs and outputs used in the process can also be used in the user program.

The modification of how the variables are assigned to the input and output channels does
not affect the user program.
Local and global variables exist. Local variables are valid in a delimited project area, in a user
program or function block. Global variables can be used in several function blocks or user
programs and can exchange data between the function blocks.
Global variables can be created at different project tree levels. Global variables are valid for all
sub-branches.
Example: If a project contains several resources, the global variables created under a resource
are only valid for the branches subordinated to that resource.
Hierarchy of the levels at which global variables can be defined.
1. Project.
2. Configuration.
3. Resource.
Values may only be written to global data in one program location! The possible sources are:

Logic in a user program.

(Safety-related) inputs.

System variables.

(Safety-related) communication protocols.
Writing to global variables at multiple positions within the program can result in unintended
effects!
In the Global Variable Editor, check the usage of global data with the Cross-Reference in
Column function.