Configuring Global Variables device structures

When defining or editing a Global Variables device, in addition to being able to configure simple variables for the Global Variables device, you can also configure user defined structures. These structures can be a single level, or they can be a multilevel, complex structure.
Once the structure is configured for the Global Variables device, you can configure a variable to use the structure as a data type.

Follow these steps to configure a structure for a Global Variables device.
The steps use the example saved AcmeProducts_Global_Variables device used in the previous configuring variables section.

  1. If you are editing a previously defined Global Variables device, make sure the Global Variables device is stopped.
  2. From the Devices tab, select the appropriate Global Variables device, and then select Edit.
    The Device window appears.

  3. Next to Structures, select Configure.
    The Structures window appears.

  4. Select Add.
    A window appears where you type the name of the structure.

  5. Type the name (for this example StructureA), and then select OK.
    The name is added to the Structures window.

    The next step is to define the fields within the structure.
  6. From the bottom of the Structures window under Fields, select Add.

    The New Variable window appears.

    The window is the same as when defining a simple variable; however, now you will be creating a variable field that will be a member of a parent structure.
  7. Type the name of the variable, and then use the Type down-arrow to select the type of data the variable will represent. For this example, the following four fields will be created:

    Variable name

    Type

    ExVar1

    INT2

    ExVar2

    INT4

    ExVar3

    FLOAT4

    ExVar4

    STRING of length 8


  8. For each field created, select Add.
    For this example, the completed Fields section of the Structures window will appear as follows:

  9. Select OK after configuring the desired variable fields in the structure.
    The Device window re-appears.
  10. Select Save to save the definition of the Global Variables device.
    Now that you have configured a structure (with four variables),  you can configure a variable that uses the structure as its data type. See Assigning a structure as a data type.