1、嵌入式系统概述宋健建南京大学软件学院2004/02/10内容n 什么是嵌入式系统n 嵌入式系统的历史和发展n 嵌入式系统的组成n 嵌入式系统的特点n 嵌入式系统软件开发1. What are embedded systems?n Definition:n Embedded system: any device that includes a programmable computer but is not itself a general-purpose computer.n Take advantage of application characteristics to optimize t
2、he design:n dont need all the general-purpose bells and whistles.A More Detailed Definitionn 国内一般定义n 嵌入式系统是以 应用为中心 ，以 计算机技术为基础，并且软硬件 可裁剪 ，适用于应用系统对功能、可靠性、成本、体积、功耗有严格要求的 专用计算机系统 。n 一般由 嵌入式微处理器 、 外围硬件设备 、 嵌入式操作系统 以及 用户应用程序 等四个部分组成，用于实现对其他设备的控制、监视或管理等功能。Embedding a computerCPUmeminputoutput analoganalog
3、embeddedcomputerExamplesn Personal digital assistant (PDA).n Printer.n Cell phone.n Automobile: engine, brakes, dash, etc.n Television.n Household appliances.n PC keyboard (scans keys).Reference Interpretation (1)n An “embedded system“ is any computer system or computing device that performs a dedic
4、ated function or is designed for use with a specific embedded software application.n Embedded systems may use a ROM-based operating system or they may use a disk-based system, like a PC. But an embedded system is not usable as a commercially viable substitute for general purpose computers or devices
5、. Reference Interpretation (2)n A specialized computer system that is part of a larger system or machine. Typically, an embedded system is housed on a single microprocessor board with the programs stored in ROM. Virtually all appliances that have a digital interface - watches, microwaves, VCRs, cars
6、 - utilize embedded systems. Some embedded systems include an operating system, but many are so specialized that the entire logic can be implemented as a single program. Reference Interpretation(3)n 中国微机学会的定义： 嵌入式系统是以嵌入式应用为目的的计算机系统，可以分为片级、板级、系统级。q 芯片级嵌入 含程序或算法的处理器q 模块级嵌入 系统中的某个核心模块板q 系统级嵌入 主计算机系统1.2 嵌入式系统历史和发展n 1971年代单片微处理器问世，它标志着嵌入式系统的开端。n 从 4个方面了解嵌入式系统历史n 硬件n 软件n 代表产品n 系统结构
