電子信息工程 外文翻譯 外文文獻 英文文獻 微處理器

1、1外文 外文資料所譯外文資料：1.作者 G..Bouwhuis, J.Braat, A.Huijser2.書名：Principles of Optical Disk Systems3.出版時間：1991 年 9 月4.所譯章節(jié)：Session 2/Chapter9, Session 2/Chapter 11原文： 原文：MicroprocessorOne of the key inventions in the history of

2、electronics, and in fact one of the most important inventions ever period, was the transistor. As time progressed after the invention of LSI integrated circuits, the technology improved and chips became smaller, faster a

3、nd cheaper. The functions performed by a processor were implemented using several different logic chips. Intel was the first company to incorporate all of these logic components into a single chip, this was the first mic

4、roprocessor. A microprocessor is a complete computation engine that is fabricated on a single chip. A microprocessor executes a collection of machine instructions that tell the processor what to do. Based on the instruct

5、ions, a microprocessor does three basic things: 1.Using the ALU (Arithmetic/Logic Unit), a microprocessor can perform mathematical operations like addition, subtraction, multiplication and division; 2.A microprocessor ca

6、n move data from one memory location to another; 3.A microprocessor can make decisions and jump to a new set of instructions based on those decisions.There may be very sophisticated things that a microprocessor does, but

7、 those are its three basic activities. Microprocessor has an address bus that sends an address to memory, a data bus that can send data to memory or receive data from memory, an RD(read) and WR(write) line that lets a cl

8、ock pulse sequence the processor and a reset line that resets the program counter to zero(or whatever) and restarts execution. And let’s assume that both the address and data buses are 8 bits wide here.Here are the compo

9、nents of this simple microprocessor:3connect either to RAM or ROM—generally both. In our sample microprocessor, we have an address bus 8 bits wide and a data bus 8 bits wide. That means that the microprocessor an address

10、 (2n) 256 bytes of the memory and it can read or write 8 bits of the memory at a time. Let’s assume that this simple microprocessor has 128 bytes of ROM starting at address 0 and 128 bytes of RAM starting at address 128.

11、ROM stands for read-only memory. A ROM chip is programmed with a permanent collection of pre-set bytes. The address bus tells the ROM chip which byte to get and place on the data bus. When the RD line changes state, the

12、ROM chip presents the selected byte onto the data bus.RAM stands for random-access memory. RAM contains bytes of information, and the microprocessor can read or write to those bytes depending on whether the RD or WR line

13、 is signaled. One problem with today’s RAM chips is that they forget everything once the power goes off. That is why the computer needs ROM.By the way, nearly all computers contain some amount of ROM (it is possible to c

14、reate a simple computer that contains no RAM—many microcontrollers do this by placing a handful of RAM bytes on the processor chip itself—but generally impossible to create one that contains no ROM).On a PC, the ROM is c

15、alled the BIOS (Basic Input/Output System). When the microprocessor starts, it begins executing instructions it finds in the BIOS. The BIOS instructions do things like test the hardware in the machine, and then it goes t

16、o the hard disk to fetch the boot sector. This boot sector is another small program, and the BIOS store it in RAM after reading it off the disk. The microprocessor then begins executing the boot sector’s instructions fro

17、m RAM. The boot sector program will tell the microprocessor to fetch something else from the hard disk into RAM, which the microprocessor then executes, and so on. This is how the microprocessor loads and executes entire

18、 operating system.Microprocessor Instructions Even the incredibly simple microprocessor shown here will have a fairly large set of instructions that it can perform. The collection of instructions is implemented as bit pa

19、tterns, each one of which has a different meaning when loaded into the instruction register. Humans are not particularly good at remembering bit patterns, so a set of short words are defined to represent the different bi

20、t patterns. This collection of words is called the assembly languages of the processor. An assembler can translate the words into their bit patterns very easily, and then the output of assembler is placed in memory for t