How to Support Multiple Screens on a Device (Windows CE 5.0)
You can use multiple display adapters to create a single, large continuous desktop that spans all the screens on your system. The larger desktop is useful because it can allow your users to display full-sized application windows side-by-side.
Windows CE provides functions that allow applications to control how they are positioned in a multiple screen system, however, the OS, based on user input, ultimately controls how windows and dialog boxes are positioned and displayed.
Hardware and Software Assumptions
- Your Platform Builder installation includes a CEPC x86 board support package (BSP).
- You have a CEPC already configured. For more information, see How to Set Up a CEPC and How to Use the IDE to Create, Customize, and Build a Run-Time Image.
- You have 2 - 4 identical display adapters, with multiple monitor support, installed in your CEPC. The ATI Rage XL Expert 98 display adapter** is the only board with a multiple monitor capable driver that ships with Windows CE.
The following table shows the steps to support multiple screens. Select the check box next to each step to track your progress.
|1. Create an empty, display-based operating system (OS) for your CEPC.||Creating an Empty Display-Based OS|
|2. Add your multiple monitor-enabled display driver to your OS design.
Keep the VGA Linear (Flat) Framebuffer display driver in your OS design.
|Adding an Item from the Catalog|
|3. Add the Catalog item Multiple Monitor Support (follow the path Core OS\Windows CE devices\Graphics and Multimedia Technologies\Graphics) to your OS design.||Adding an Item from the Catalog|
|4. Edit your OS design's registry to reflect the number of display adapters in your system:
|5. Set Platform Builder to build the type of run-time image you want.||Levels of Debugging Support|
|6. Build your run-time image.||Building a Run-Time Image|
|7. Configure your download and debugging connections.||Configuring a Connection for Downloading and Debugging|
|8. Download the run-time image to the CEPC.||Downloading a Run-Time Image|
|9. After your run-time image is loaded, start a windowed application and open a dialog box. Move them around to see how they transition from one screen to another.
**The non-Microsoft software and hardware referenced in this document are included for illustrative purposes only. Illustrations that use such third party software and hardware as examples are not intended to be an endorsement or recommendation of any of these products. We provide this information only as a convenience for our customers for purposes of explaining a practical application and do not provide warranties of any kind, whether express, implied or statutory, including but not limited to the implied warranties of merchantability and/or fitness for a particular purpose.
Note Internally, your OS enumerates the display adapters in the order they appear on the PCI bus. The OS considers the first display adapter on the PCI bus to be the primary display adapter. Each subsequent display adapter extends the screen area to the immediate right of the area controlled by its predecessor on the PCI bus.
The taskbar is only displayed on the screen attached to the primary adapter. It is not possible to extend the desktop area above or below the primary screen.
After your OS loads, you might find that your Windows CE desktop appears out of sequence compared to the physical layout of your screens. For example, the left half of your desktop may appear on your right screen and the right half of your desktop may appear on the left screen. There is no way to compensate for this with software settings in your OS. You must physically rearrange your hardware.
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