Command 'Interface Editor'

Symbol: ; keyboard shortcut: Alt+F6.

Function: The command opens and closes the Interface Editor tab above the visualization editor.

Call: Menu bar: Visualization ‣ Interface Editor Also by clicking on the small down arrow at the top of the visualization editor

Tab 'Interface Editor'
Scopes

Tab 'Interface Editor'

Symbol:

The tab contains an editor for the declaration of interface variables. The editor behaves in a similar way to the declaration editor of a function block, however interface variables are not initialized.

Syntax

<scope>
    ( {attribute '<attribute name>' ( := '<expression>' )? } )?
    <identifier> : <data type>;
END_VAR

<scope> : VAR_INPUT | VAR_OUTPUT | VAR_IN_OUT
// (...)? : Optional

Example

Declaration in the interface editor

VAR_INPUT
        {attribute 'parameterstringof'}
        sIdentifier : STRING; // String for instance name
        iCounter : INT;
END_VAR
VAR_IN_OUT
        {attribute 'VAR_IN_OUT_AS_POINTER'}
        fbController: FB_Controller;
END_VAR

Scopes

Possible scopes for interfaces of visualizations or dialogs

VAR_IN_OUT

When transferring a structure

When the visualization is instanced, it gets a reference to the current application data.
When transferring a control variable, if the variable is written to when a user input is made. Only then can the visualization write to it.

Note: In the case of dialogs, the data is written back only when the dialog is closed.

Hint: We strongly recommend that you use this scope so that the return of values is possible. Moreover, no data needs to be copied.

VAR_IN_OUT

Pragma {attribute 'VAR_IN_OUT_AS_POINTER'}

When transferring a pointer to a data object

In contrast to the VAR_IN_OUT scope (without an attribute), the variable changes are effective immediately and not just when the dialog is closed.

Note: Use this scope only if the visualization implements a Dialog.

VAR_INPUT

When transferring data that will only be read

Note:

If the visualization is executed as an integrated visualization, then only input variables of a basic data type (scalar type) are permitted to be transferred.
If the visualization is executed as a CODESYS TargetVisu or a CODESYS WebVisu, then input variables of any data type (including POUs) can also be transferred.

VAR_INPUT

Pragma {attribute 'parameterstringof'}

When transferring a variable (data type STRING) for the instance name of the transfer parameter specified in the attribute