2024年1月6日发(作者：)

VISUAL SUMMARY

视觉摘要

THE SYSTEM UNIT

系统单元

System unit(or system cabinet) contains electronic components. Four basic types are: desktop,

notebook, tablet PC, and handheld. PDA(personal digital assistant) is the most widely used

handheld computer.

系统单元（含电子元件或系统的公司）。基本类型是：炉桌面，笔记本电脑，平板电脑和手持。PDA（个人数字助理）is the most widely used手持计算机.

Electronic Representation

电子表示

Our voices create continuous analog signals. A conversion to digital signals is necessary before

processing. Data and instructions can be represented electronically with a two-state or binary

system of numbers(0 and 1). Each 0 or 1 is called a bit. A byte consists of eight bits and represents

one character.

我们的声音创造了连续的模拟信号。前处理是必要的转换为数字信号。数据和指令可以表示用状态或二进制数字（0和1）。每个0或1称为一位。一个字节包含八位代表一个字符。

Binary Coding Schemes

二进制编码方案

Binary coding schemes convert binary data into characters. Three such schemes are

二进制编码方案，将二进制数据转换为字符。三个这样的方案有

● ASCII—the most widely used for microcomputers.

●ASCII——最广泛使用的微型计算机。

● EBCDIC—developed by IBM; used primarily by large computers.

●EBCDIC —IBM开发的；主要用于大型计算机。

● Unicode—16-bit code; originally designed to support international languages like Chinese and

Japanese.

Unicode——16-bit代码；最初设计为支持像中国和日本的国际语言。

SYSTEM BOARD

系统板

The system board(motherboard) connects all system components and allows input and output

devices to communicate with the system unit. It is a flat circuit board covered with the system

unit. It is a flat circuit board covered with these electronic components:

系统板（主板）连接所有系统组件和允许的输入和输出设备与系统通信。这是一个平坦的电路板覆盖系统单元。它是一块被这些电子元件覆盖的电路板：

●Sockets provide connection points for chips (silicon chips , semiconductors, integrated

circuits).Chips are mounted on carrier packages.

●插座芯片提供连接点（硅芯片，半导体，集成电路）芯片安装在载体封装。

●Slots provide connection points for specialized cards or circuit boards.

●槽提供专门的卡或电路板的连接点

●Bus lines provide pathways to support communication.

●公交线路提供途径支持通信。

To be a competent end user, you need to understand how data and programs are represented

electronically. Additionally, you need t understand the functionality of the basic components in

the system unit: system board ,microprocessor, memory, system clock, expansion slots and cards,

bus lines, and ports and cables.

做一个合格的最终用户，您需要了解的数据和程序以电子方式。此外，你还需要了解在系统单元的基本部件的功能：系统板，微处理器，存储器，时钟系统，扩展插槽和卡，公交线路，和端口和电缆。

MICROPRCESSOR

微处理机

The microprocessor is a single chip that contains the central processing unit(CPU) or

microprocessor. It has two basic components:

微处理器是一个单芯片，包括中央处理单元（CPU）或微处理器。它有两个基本组成部分：

● Control unit tells the computer system how to carry out program instructions.

● 控制单元告诉计算机如何执行程序指令。

● Arithmetic-logic unit (ALU) performs arithmetic and logical operations.

● 算术逻辑单元（ALU）的算术和逻辑操作的行使。

Microprocessor Chips

微处理器芯片

A word is the number of bits that can be accessed by the microprocessor at one time. Older

microprocessors process data and instructions in microseconds; newer ones process in

nanoseconds. Supercomputers process in picoseconds.

一个字的位可以在同一时间通过微处理器访问数。在微秒以上微处理器过程数据和指令；更新的过程在纳秒。超级计算机在皮秒内审核。

The two most significant developments are 64 bit and dual-core chips. Parallel processing

requires programs that allow multiple processors to work together to run large complex

programs.

两个最重要的发展是64位的双核心芯片。并行处理要求，允许多个处理器协同工作，运行大型复杂的程序。

Specialty Processors

专业处理器

Specialty processors include graphics coprocessors (process graphic images), smart cards(plastic

cards containing embedded chips), processors in automobiles (monitor fuel efficiency, satellite

entertainment, and tracking systems), and RFID tags (track merchandise).

专业的处理器包括图形协处理器（过程图形图像），智能卡（含嵌入式芯片的塑料卡），处理器（监测汽车的燃油效率，卫星娱乐，和跟踪系统），和RFID标签（跟踪商品）。

MEMORY

存储器

Memory holds data, instructions ,and information . There are three types of memory chips: RAM,

ROM, and CMOS.

存储器存储数据，指令和信息。有三种类型的存储器：RAM，ROM，和CMOS。

RAM

随机存取存储器

RAM(random-access memory) chips are called temporary or volatile storage because their

contents are lost if power is disrupted.

RAM（随机存取存储器）芯片是因为我喜欢他们或挥发性存储contents are is if disrupted失去电力。

● Cache memory is a high-speed holding area for frequently used data and information.

● 高速缓冲存储器是一种为经常使用的数据和信息的高速暂存区域。

● Flash memory is a special type of RAM that does not lose its contents when power is

disrupted .

● 闪存是一种特殊类型的RAM的内容不会丢失当电源中断。

● Virtual memory divides large programs into parts that are read into RAM as needed.

● 虚拟内存将大型程序划分多个部分读入内存需要的。

ROM

只读存储器

ROM(read-only memory)chips are nonvolatile. Storage and control essential system operations.

ROM（只读存储器）芯片是易失性。存储与控制系统操作。

CMOS

互补金属氧化物半导体;

CMOS (complementary metal-oxide semiconductor) chips provide flexibility and expandability to

computer systems.

CMOS（互补金属-氧化物半导体芯片提供的灵活性和可扩展性）到计算机系统。

SYSTEM CLOCK

系统时钟

System clock controls the speed of operations. Clock Speed is measured in gigahertz(GHZ).

系统时钟控制操作的速度。时钟速度是衡量千兆赫兹（GHz）。

EXPANSION SLOTS AND CARDS

扩展插槽和卡

Most computers allow users to expand their systems by providing expansion slots on their system

boards to accept expansion cards.

大多数计算机允许用户通过提供扩展槽上的系统板接受扩展卡扩展他们的系统。

Examples of expansion cards include graphics card, sound cards, modem cards , network

interface cards (NIC; network adapter cards), TV tuner cards, and PC cards.

扩展卡的例子包括显卡，声卡，网卡，网络接口卡（网卡；网络适配器卡），电视调谐器卡，PC卡。

Plug and Play is a set of hardware and software standards designed to assist with the installation

of expansion cards.

即插即用的是一套硬件和软件设计来协助扩展卡安装标准。

BUS LINES

公交线路

Bus lines, also known as buses, provide data pathways that connect various system components.

Bus width is the number of bits that can travel simultaneously.

公交线路，也被称为总线，提供数据通路，连接各种系统组件。总线宽度是位的，可以同时数。

Expansion Buses

扩展总线

System buses connect CPU and memory. Expansion buses connect CPU and slots .Five principal

expansion bus types are ISA (industry standard architecture), PCI(peripheral component inter

connect), AGP (accelerated graphics port), USB (universal serial bus), and FireWire bus.

系统总线连接CPU和内存。扩展总线连接CPU和插槽。五主扩展总线类型是ISA（工业标准结构），PCI（外围组件互连），AGP（加速图形端口），USB（通用串行总线），和火线总线。

PORTS

端口

Ports are connecting sockets on the outside of the system unit .Some ports are standard while

others are more specialized.

端口连接在系统单元的外部插座。一些端口的标准而其他的更专业。

Standard Ports

标准的端口

Four standard ports are

四个标准端口是

● Serial—send data one bit at a time.

● 串口——发送数据一次一位。

● Parallel—send eight bits simultaneously.

● 并口——同时发送8位

● USB (universal serial bus) —faster; one port can connect several devices to system unit.

● USB（通用串行总线）-更快；一个端口可以连接多个设备的系统单元。

● Fire Wire— as fast as USB 2.0 ports; provide connections for specialized FireWire devices.

The two most significant recent developments in ports and buses are PCI express (PCIE) and serial

ATA(SATA).

●火线——和USB 2.0端口一样快；为专业的火线设备提供链接。

最近事态发展的两个端口和总线是PCI Express（PCIe）总线和串行ATA（SATA）。

Specialize ports

特殊端口

Two specialty ports are

两个特殊的端口是

● MIDI(Musical instrument digital interface)—special port for musical instruments such as

electronic keyboards.

● 你的MIDI（乐器数字接口）接口的这样一个特殊的电子键盘乐器。

● IDA(Infrared Data Association) ports—provide wireless connections.

● IDA（红外数据协会）端口——提供的无线连接

Cables

电缆

Cables are used to connect external devices to the system unit via ports.

电缆通过端口用于连接外部设备到系统单元。

POWER SUPPLY

电源

Power supply units convert AC to DC; they are located within the desktop computer’s system unit.

AC adapters power notebook computers and tablet PCs and recharge batteries.

电源单元将交流电转换为直流；他们位于桌面计算机的系统单元。交流适配器电源笔记本电脑和平板电脑和充电电池。

CAREERS IN IT

在IT职业中

Computer technicians repair and install computer components and systems. Certification in

computer repair or associate degrees from vocational schools required. Hourly wage $13.00 to

$22.00.

电脑技术人员维修及安装计算机部件和系统。在电脑维修或从职业学校要求学士学位证书。每小时工资13美元至22美元。