Data Binding Editor

Help Contents


A Data Binding is an IEC 61131-3 Expression that links the visual appearance of something to a changing data source.

The IEC 61131-3 Expression can be a simple tag reference, for example:

%"Folder.Analog Data Point Tag"

The IEC 61131-3 Expression can also be a more complex expression, for example:

( %"Folder.Temperature Celsius" * 9.0 / 5.0 ) + 32.0

Features that Use Data Bindings

These features use data bindings:

FeatureExample Property
Graphic Editor The Graphic Editor uses data bindings to link the appearance of items on a graphic page to tags in the database. For example:
  • The DataBindText property links the text displayed to an expression.
  • The DataBindFillColor property links the fill color to an expression. This can be used to indicate different equipment states using different colors.
  • The DataBindRotationSpeed property links the speed of rotation to an expression.

See Graphic Editor Data Bindings for the list of available data bindings.

Toolbar Editor The Toolbar Editor uses data bindings to manage the appearance of buttons on the Operator Interface Toolbar. For example:
  • The DataBindEnable property chooses whether a toolbar button is enabled (shown normally) or disabled (dimmed).
  • The DataBindTooltip property defines the text to display when the operator hovers the mouse over the toolbar button.
Button appearance can be linked to tags in the database or the current page on display.

Editing Data Bindings

To edit a Data Binding:

  1. Use one of these methods to select an item:
  2. In the Properties Window select a property from the Data Bindings group, for example DataBindColor.
  3. Click the Browse button Property browse button to open the Data Binding Code Editor.
  4. Edit the Data Binding Code.
  5. Press OK to confirm the changes.

Note: If there are syntax errors in the Data Binding Code, the editor will not accept the changes when you press the OK button. Either correct the errors, or press the Cancel button to cancel the changes.


When the Data Binding Editor is open, press Ctrl+Spacebar to open the autocomplete list to provide suggestions depending on the context:

Autocomplete menu

The autocomplete list shows:

To select an item from the autocomplete list, do one of the following:

To insert the autocomplete reference into the code, do one of the following:

Inserting a Tag Reference

You can insert tag references directly into the code editor using the Insert Tag Reference... command:

Text editor context menu

Choosing the Insert Tag Reference... command opens the tag browser allowing you to select a tag reference directly:

Tag reference browser

Finding and Locating Errors

Syntax errors in Data Binding Code are highlighted in the editor using a dashed red underline:

Data Bindings showing syntax error

Note: If you move the cursor near the error, a tooltip will be displayed providing an explanation of the error.

Finding more Subtle Errors

The Data Binding Code Editor will not accept code with obvious syntax errors. It is still possible to enter code with more subtle semantic errors. To find and locate additional errors:

  1. Switch to the Code Errors tab of the Status Monitor Window:
    Status views showing code errors

    Note: The above message indicates an invalid parameter for the ROUNDSD Function.

  2. Click the link to the error. The Configuration Tool will select the item on the canvas and highlight the property with the error in the Properties Window:
    Properties window showing error

    Note: The property with the error is shown with red text.

  3. Click the Browse button Property browse button to open the data bindings text editor:
    Data Bindings showing semantic error

    Note: If you move the cursor near the error, a tooltip will be displayed providing an explanation of the error.

Further Information

Graphic Editor

For information on using the graphic page editor.

Toolbar Editor

For information on using the operator toolbar editor.

Properties Window

For information about editing properties of items using the Properties Window.


For the meaning of terms used in Fernhill SCADA.