Did you know that Microsoft� Windows� CE 3.0, which the Pocket PC uses, supports real-time task switching between applications? This article explains what real-time multitasking is and how it improves the Pocket PC.

What Is Real-time Task Switching?

Real-time task switching is loosely defined as the ability of the operating system to switch tasks in approximately 50 milliseconds or less. Real time task switching is normally required by some embedded systems that need real fast responses to events. The prior release of Windows CE, version 2.11, switches tasks in about 250 milliseconds. Windows CE 3.0 on the Pocket PC is much faster, which makes the system run smoother.

How Does the Pocket PC Benefit from Support of Real Time?

Did you know that your Pocket PC is running multiple tasks even when just displaying the Today screen? These tasks are the kernel, shell, and GDI (Graphics Display Interface) -- in addition to any applications you are using. The Pocket PC is constantly switching between these tasks, and between other programs you are running simultaneously. This means that there are many times while you are using your Pocket PC when it has to switch between applications, in order for it to finish a function call, a processor activity. Each time a switch occurs, the amount of time the Pocket PC takes to switch is about one fifth the amount of time that the Palm-size PC took.

Windows CE uses preemptive multitasking to guarantee that all applications will have a percentage of the CPU. Preemptive multitasking means that Windows CE maintains a list of tasks that are running and provides a guarantee that those applications will have a percentage of the CPU. This allows you to run other applications in the background on your Pocket PC while you run the application that you are working with.

Applications That Benefit from Real Time

The time savings add up to benefits that everyone can see. Each time you run an application and switch to another, the system responds faster than it ever has before. This is really noticeable in applications that are time sensitive, such as the Windows� Media Player, which would skip parts of the music if it were interrupted for a long period of time. With real-time switching, you can run other programs while playing music. It also allows for faster and smoother playback of videos on Pocket PCs with video players, such as the Casio E-115 using the Casio Video Player. Other Pocket PCs are able to play back MPEG videos using Pocket TV. You will also notice smoother game playing in graphics-intensive games as well.

Conclusion

Real-time task switching enhances your ability to use your Pocket PC by making it faster and more efficient. This really makes a difference for applications that are very CPU-intensive -- such as video players, Primer, games, and Windows Media Player. This invisible enhancement makes the Pocket PC more enjoyable to use.