摘要
后PC时代，嵌入式系统在计算机的应用中日益发挥重要的作用。嵌入式系统被定义为：以应用为中心、以计算机技术为基础、软件硬件可裁剪、适应应用系统对功能、可靠性、成本、体积、功耗严格要求的专用计算机系统，因此嵌入式系统主要由嵌入式处理器、相关支撑硬件、嵌入式操作系统及应用软件系统等组成。本文所述的嵌入式系统是基于ARM核的PILLIP微处理器，在相关通信硬件、外围设备(如LCD，FLASH)的支撑下，在无线通信专用的嵌入式操作系统平台下的系统。
本文首先介绍了嵌入式系统，嵌入式处理器的发展与应用，嵌入式操作系统，嵌入式系统的发展，国内移动终端的发展近况以及本文的理论与实践背景；接着阐述了系统的总体结构，概略介绍了嵌入式操作系统提供的服务和各个模块的功能；随后详细介绍了基于FLASH的嵌入式文件系统的目标、功能、设计思想和实现，外围设备的驱动程序的设计与实现，重点介绍了LCD、键盘的驱动程序的目标、功能和设计以及本系统人机接口(MMI)的中心支撑软件模块MMI引擎的设计与实现，它为MMI程序员完成菜单功能的实现提供了有力的支持。
论文的主要工作成果在于：实现了一个基于FLASH的文件子系统，在MMI中采用了MCC机制增强了软件的可扩展性以及在DRIVER部分各模块都分成Handler层和Driver层为软件二次开发提供了方便。
The embedded system is playing the more important role in computing application increasingly in post_PC age. It is defined as the special computer system which is oriented to application, base on computer technology, is apt to select software or hardware and is fit in function and reliability, so the embedded system is usually made up of micro processor, related hardware, embedded operation system, application software, and so on. The embedded system of this paper bases on microprocessor of ARM, the related hardware, peripheral equipments (such as the LCD, FLASH) and the special operation system in wireless communication.
In this paper, embedded system will be introduced firstly, including the definition of the embedded system, development and application of microprocessor in embedded system, the category , history and development of the embedded operation system. Architecture of the system will be discussed secondly , including the service of the operation system and the function of all models; The file server system which bases on FLASH is the core model, the paper describes its design purpose , architecture and function. The driver software model, especially on LCD, keyboard will be described too; Finally I will discuss the MMI engine that provides the service for the MMI programmer to complete the menu function.
The main contribution of this paper is designing and realizing of a file system that bases on FLASH. The MCC in MMI boosts up expansibility of the software. The separation between handler and driver in DRIVER provides the convenience for second development of software.
引文
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