2 Fundamentals of Computer Hardware.ppt

Unit 2 Fundamentals of Computer Hardware Organization of Computer System Components A computer is a fast and accurate symbol manipulating system that is organized to accept, store, and process data and produce output results under the direction of a stored program of instructions. 计算机是一种可用于接收、存储和处理数据，并产生输出结果的快速、精确的符号加工系统，由存储的程序指令控制工作。 This section explains why a computer is a system and how a computer system is organized. 本节介绍为什么计算机是一个系统、以及计算机系统是如何构成的。 A computer system combines two basic parts: hardware and software. As shown in Fig.2-2, some input devices allow direct human/machine communication, while some first require data to be recorded on an input medium such as a magnetizable material. The keyboard of a workstation connected directly to or online to a computer is an example of a direct input device. Regardless of the type of device used, all are components for interpretation and communication between people and computer systems. Computer data storage provides one of the core functions of the modern computer, information retention. It is one of the fundamental components of all modern computers. As Fig. 2-3 shows, there are three main sections found in the CPU of a typical personal computer (PC) system: the arithmetic-logic section, the control section and the registers. OUTPUT DEVICES. Like input units, output devices are instruments of interpretation and communication between humans and computer systems of all sizes. These devices take output results from the CPU in machine-coded form and convert them into a form that can be used by people (e.g. a printed and/or displayed report) or as machine input in another processing cycle. In personal computer systems (See Fig. 2-2), display screen and desktop printers are popular output devices. Larger and faster printers, many online workstations, and magnetic tape drives are commonly found in larger systems. This terminology refers to the fact that although these devices are not a part of