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With the functions of the basic functions of the promotion of the development of communication technology and 3G networks, is not just a simple voice phone, send and receive SMS, mobile office, mobile entertainment to people of all ages. PDA (Personal Digital Assistant) It is in this context, and to grow and develop, it not only integrates the basic functions of the traditional phone is also compatible with many of the features of the laptop, and truly meet user needs. The PDA market has great potential, the personal terminal technology trends. Embedded PDA, The Design and Implementation of the terminal based on embedded Linux and Qt / Embedded graphical interface, and eventually build a personalized interactive system for the PDA. The main content of the paper include: (1) several popular embedded processor, embedded operating system, GUI graphics support system advantages and disadvantages of the discussion, combined with device characteristics selected for the ARM9 core S3C2410-based system hardware platform, 2.4.18 kernel Linux and Qt as system software platform. (2) to establish a hardware development platform, s3C2410 processor, and peripheral interface components analysis introduction about their structure and function; (3) made an in-depth study of the Linux kernel and file system. A detailed analysis of the Linux system bootloader function as well as it is compiled and transplantation; shearing of the Linux kernel, compile and transplantation; production of the Linux file system, compiler and transplantation for system developers to build software platform. (4) were established on the basis of the analysis of Qt / Embedded System Qt development and debugging environment on the PC, and Qt compiled on cygwin transplant environment. (5) under the Qt development environment in the PC, developed several applications based on Qt / E has a friendly interface. The use of these programs to build their own graphical interface system, compiled on cygwin transplanted into the target board, stable operation. Verify the validity of Linux Qt / Embedded C development environment. Finally, the development of a set of beautiful and efficient results, touch interactive system, it has good portability, simple operation and ease of secondary development. This paper is divided into four blocks detailed above: First of all, according to the needs of the system, the hardware platform to build the embedded system development. The system provides a variety of applications in an embedded PDA with touch screen LCD module to achieve human-computer interaction and video playback, you need a network interface to achieve the target machine remote login and resource downloads, need to debug UART serial port target machine, you need JTAG interface to download the program, you need the audio controller to play mp3 audio format files, large NandFlash memory to store audio and video files. In this paper, the system requirements, compared by analyzing the performance of various components, respectively, of processors, memory chips, audio chips, network chips, LCD selection. Final choice the S3EB2410 development board as the hardware platform of the system running, do in-depth analysis and the design of peripheral circuits. Second, building embedded systems software development environment. The comparative analysis of common embedded operating system, chose embedded Linux as the operating system, because the system hardware devices have a wide range of support, the kernel high degree of stability, the source code is open and free, and many other advantages . Describes the composition of the Linux system, transplant characteristics, the establishment of a cross-compiler environment, analyzing the working mode of the Bootloader paper selection VIVI VIVI start as a boot loader, then compile, configure, transplanted into the target board . Linux kernel structure learning, and compile, cutting, and configuration for the system kernel, transplanted into the target board. With busybox produced the project the file system Cramfs file system, and compile transplanted into the target board. Then, to learn the characteristics of the GUI, come to the requirements of the embedded device GUI: small size, lightweight, quick start, occupy less system resources, portability, high reliability. By contrast mainstream GUI features, this choice of Qt / Embedded graphical interface system, because it is easily extensible and C compatibility. Qt display in-depth understanding of the mechanism for inter-process communication mechanism, built on a PC on Qt / E debugging environment for program debugging Correction own series, established in cygwin compile transplant environment for Qt / E own series graphics program for the ARM architecture program, which can be downloaded to the target board. Finally, Qt / E design process to study the relationship and the role of the main Qt library class inheritance. Follow design ideas, develop their own clock, MediaPlayer player, file viewer, tape recorders and other applications. Debugging success on the PC, and transplanted into the target board to run stable. Develop their own application software to build personalized graphical interface system, the file system add Qt catalog, change and add files, and a graphical file system, the compiled transplanted into the target board running well.
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