Operating system Windows Phone
Plan
Windows Phone Platform
Windows Phone Processor
Operating system Windows Phone
Graphic screen
Windows Phone Processor
Touch screen
Camera
Devices for locating and moving
Hardware buttons
Memory and storage
Windows Phone Ecosystem
Zune Multimedia Management Software
Windows Live and Xbox Live Services
Bing Maps
Development of applications for Windows Phone
Windows Phone Emulator
Software access to Windows Phone tools
Silverlight and XNA
Windows Phone Platform
Nowadays computers take part in almost all spheres of life. Mobile phones are no exception. The device on the Windows Phone platform can be considered a computer that can make phone calls, and not just a phone that can run programs.
The characteristics of devices on the Windows Phone platform are similar to computers: a powerful processor, a local data store, high-performance 3D graphics and a lot of RAM. The management of the device and programs running on it is carried out by its own operating system, which can be compared with the Windows operating system for desktop computers: it starts when the computer is turned on, and at the end of the operation turns off the computer.
The Windows Phone 7 series differs significantly from previous versions of devices running the Windows Mobile operating system. In Windows Mobile, you could create programs and run them on earlier versions of the operating system, but you did not use the Silverlight or XNA environment. Number 7 in the product name means the 7th incarnation of the Windows Mobile operating system platform. This does not mean that it is based on the Windows 7 operating system, but you can run the Windows Phone program on a Windows-based computer. Support for Silverlight and XNA does not break ties with the past, but is a balanced mix of continuity and innovation.
Hardware requirements for devices on Windows Phone 7 are quite serious for mobile devices. All Windows Phone devices must meet certain minimum requirements, but phone manufacturers can produce devices with a large amount of memory, a faster processor, a hardware keyboard and a larger screen. At the same time, the device may not have a hardware keyboard - most devices will have a screen keyboard. When creating programs on XNA developers will have to get used to such changes in the hardware. However, the platform includes several devices, especially useful in game development, for example, an accelerometer and a touch screen.
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Windows Phone Processor
The central processor (CPU) of the computer is the device that performs all the work. When the program starts, the central processor is responsible for retrieving data from memory, changing and returning data. The most common characteristic of the speed of the computer is the processor clock speed. The central processor includes a clock that counts the bars during operation. At one clock cycle, the CPU can perform one part of the low-level operation: retrieving instructions from memory, performing computation, and so on.
The higher the clock speed, the faster the processor is running. The processor clock speed of modern desktop computers is within 3 GHz (about 3 thousand billion times per second). This means that one cycle lasts approximately one nanosecond. During this time, the signal can travel a distance of about 30 cm. The time for which signals can pass through the circuit is a serious limiting factor.
The processor frequency in Windows Phone is about 1 GHz. We can assume that the speed of Windows Phone is approximately equal to the third part of the speed of the computer. But in practice this is incorrect for several reasons.
First, the clock frequency is not comparable between the processors of the computer and the mobile device. The computer processor can do five steps for what the Windows Phone processor needs ten clock cycles. The computer processor can perform many operations on the hardware (for example, floating point operations), for which the Windows Phone processor usually requires a subroutine call, which will be performed much more slowly.
Secondly, the computer can have several processors. This does not mean that a computer can run faster, but processors can process more data at one time. Windows Phone devices include only one processor.
Finally, the computer is almost not limited to power. The CPU of the computer can run at the maximum speed for as long as necessary. At the same time, there is a problem related to the fact that the processor must be cooled all the time. The faster the processor is running, the more energy it consumes. If the phone's processor were running at maximum speed all the time, then the battery life would be very short. The phone's operating system speeds up and slows down the processor depending on what operations it should perform at the moment. Although the phone is a fast processor, it is used at full capacity only when the phone must perform actions that require a very fast response.
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Thus, when creating a program for Windows Phone, the processing power of the processor is not an unlimited resource. Programmers for Windows Phone should remember that applications should be easy to use and should not lead to a rapid depletion of the phone's battery.
Operating system Windows Phone
The operating system Windows Phone 7 is not based on the Windows 7 operating system for desktop computers. The Windows Phone operating system is a development of the Windows CE (Compact Edition) system, which was specifically designed to work on portable computer systems and optimized for performance and saving the battery life of the device. However, the program will work in Windows Phone as well as on the computer.
Graphic screen
The Windows Phone screen has a high resolution and contains a large number of pixels. It allows you to use graphics of high quality and allows you to display a large amount of text. The more pixels there are on the screen, the higher the image quality that can be displayed. However, the more pixels in the image, the more memory is needed to save the image, and the computer must perform more operations to redraw the image on the screen. This is especially important for a mobile device, since increasing the performance of hardware means more power consumption and shortens battery life. Selecting the screen resolution is a trade-off between the battery life, the cost of its manufacture and the screen brightness (the smaller the pixels, the lower the screen brightness).
In the current version of Windows Phone, the screen resolution is 800 * 480 pixels. It can be used in landscape or portrait orientation. The phone has an accelerometer that determines the position of the phone. Operating system Windows Phone can adjust the image in accordance with the orientation of the phone.
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The developer can specify which screen orientation the application supports. By default, Silverlight applications are displayed in portrait mode, but you can make them adapt themselves to screen orientation changes. Specifically, new events are provided for detecting the change of orientation, and some changes are handled automatically. Game developers usually specify a specific orientation of the user's screen. Programs on XNA use landscape mode by default, but this property is easy to override.
Developers of applications for phones often face the problem associated with a large number of screen sizes of different devices. Usually the program needs to be adjusted for each available screen size. Windows Phone hardware can scale the application screen to the physical screen size of the device. This feature can improve the performance in games and allows you to create games that look the same on any device.
Windows Phone Processor
In the very first computers, all the work was done directly by the central processor. Among the tasks that are performed is the output of the image on the screen. Later, all the work on the output of images on the screen began to perform a specialized device for controlling the screen - a graphics processor (GPU). Advanced graphics processors support 3D graphics and can perform operations on floating point numbers and over matrices. They also contain pixel shaders that can be programmed to process images at each point of the screen at high speed, including rendering, adding lighting effects and blur, and so on.
Until recently, graphics processors were only in desktop computers and game consoles, but now they appeared in mobile phones. The Windows Phone platform contains a chip for processing graphics, which is used to create 3D effects on the phone screen and can also be used in the XNA game design environment to create fast 3D games.
Touch screen
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Older portable devices used resistive touch screens. When the user touches the resistive screen, its plastic surface bends and acts on the lower level. The point of contact is determined on the basis of information on the change in electrical resistance at the contact boundary. Resistive touch screens are cheap to manufacture and work well with the stylus. However, this principle of operation makes it difficult to detect several simultaneous touches. It is also difficult to make a resistive screen of solid material, for example glass, because the screen should bend to create a contact that defines the entry point.
The capacitive touch screen works differently. The sequence of conductors under the screen surface fixes the change in capacitance that occurs when touching. Based on this information, the hardware of the touch screen decides where the touch input occurred on the screen. The cost of manufacturing capacitive touch screens is higher than resistive, because they require additional hardware to process input signals, but sensor circuits can be placed on the back of the glass screen to make the screen more rigid. The capacitive touch screen is not as accurate as the resistive when using a stylus, but a capacitive screen can detect several simultaneous screen touches.
In all Windows Phone devices, a capacitive touch screen can track at least four touches. The transition to multi-touch input is an important step in the development of mobile devices. The user can control the software using multi-touch gestures. The Windows Phone operating system has a means for recognizing gestures that can be used in programs.
Camera
Virtually all mobile devices have cameras - and Windows Phone is no exception. The phone is equipped with a camera with a resolution of 5 megapixels and flash, which is comparable to the resolution of a digital camera. 5-megapixel images can be printed on photo paper in 13 * 18 cm format in good quality.
Applications for Windows Phone can control the camera and use it to create snapshots or video streams. Applications can also directly access the video stream and add additional objects to the playback or detect certain elements, such as barcodes or faces in photos. The user can save the taken pictures in the phone as multimedia content. Programs can open these images and work with them.
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