计算机输入输出

计算机输入输出(中文3500字,英文2300字)
访问计算机
计算机是把数据处理成信息的机器。除非有些人需要信息，否则就不存在处理数据。没有数据，也就没什么要处理的。输入和输出设备为人们访问计算机提供了手段。本文要讨论一些I/O设备，然后示出这些设备是如何与计算机实际连接的。
基本的I/O设备
键盘和显示器
大多数小型计算机系统基本的输入设备是键盘。当键入字符时，字符就存入主存中，然后再把它从存储器复制到基本的输出设备——显示器。事实上，显示器通常称为监视器，作为主存的一个窗口，允许用户查看它的内容。

Computer’s Input and Output
Accessing a Computer
A computer is a machine that processes data into information. Unless some human being needs the information, there is no point to processing the data. Without data, there are nothing to process. Input and output devices provide a means for people to access a computer. In this chapter, we’ll consider a number of input and output devices and media, and then show how they are physically linked to a computer.
Basic I/O
Keyboards and Display Screens
The basic input device on most small computer systems is a key-board. As characters are typed, they are stored in main memory, and then copied from memory to the basic output device, a display screen. In effect, the screen, often called a monitor, serves as a window on main memory, allowing the user to view its contents.