Watlow Silver Series - Manual (Page 129)

Creating Windows 121
Assigning Underlay Windows
An Underlay Window is a Base Window that is displayed at the same time as the Base Window that calls it. Each full-
size Base Window can display up to three underlay windows. A popup window cannot display any underlay windows.
There may be times when it is desirable to place the same information on multiple (but not all) windows. Underlay
windows provide a means to accomplish that without the overhead of a Direct or Indirect Window, and without using
the Common Window (which makes the information visible on all windows). Underlay windows also eliminate the
need to actually place the same objects on multiple windows, which increases the memory required for the project.
Each base window can display up to three underlay windows, which are called Bottom, Middle, and Top.
How to Display Underlay Windows
When you have common objects to display on multiple screens, use the underlay window feature to store these on
underlay windows attached to a base window. This decreases the amount of memory required for the project. The
base window “calls” the underlay window. Each full-size base window can display up to three underlay windows,
which are called Bottom, Middle, and Top. Objects on the underlay windows cannot be edited from the base window
on which they are displayed.
 It may be desirable to use Underlay Windows but temporarily hide them when developing the project.
The button on the Standard Toolbar toggles the visibility of objects on Underlay Windows.
 A popup window cannot display any underlay windows.
To assign underlay windows to a base window, you must first create the underlay windows. Underlay windows are
created the same way base windows are created. Then you can assign the underlay windows to the base window.
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To assign underlay windows to a base window:
1. From the Window menu, select Open Window. The Open Window dialog box appears.
2. Highlight the base window you wish to use.
3. Click the Settings… button. The Window Setting dialog box appears.
4. Click the pull-down list box for each Underlay window selection to assign the underlay window screens to the
base window.
5. Click OK. Click Close on the Window Setting dialog box.
Rules That Apply to Underlay Windows
• Only the objects of an underlay window are displayed on the base window. All background
information about the underlay window (i.e. background color, frame color and size, etc.) are not
displayed on the base window.
• Active objects can be ‘overlaid’ on top of each other over two or more underlay windows. For
example, a Set Bit object that is configured to set an HMI local bit LB0 is located at X=20, Y=50 for
Underlay Window #1. Another Set Bit object that controls LB1 is placed on Underlay Window #2 at
the same location. When the Base Window displays these two windows, both objects will be active
so that when they are pressed both LB0 and LB1 will be set.
• Static objects may be overlaid using underlay windows. However, any static object that is on the
Base Window has the highest precedence and will be displayed over any static objects that are on
the underlay windows. Active objects have higher precedence over static objects.
• Popup windows cannot display underlay windows.
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