電子信息工程 微處理器 外文翻譯 外文文獻(xiàn) 英文文獻(xiàn)

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(shí)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 e

2、lectronics, 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 an

3、d 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 micr

4、oprocessor. 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 instructi

5、ons, 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 can

6、 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 clo

8、ck 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 compon

9、ents of this simple microprocessor:1. Registers A, B and C are simply latches made out of flip-flops.2. The address latch is just like registers A, B and C.3. The program counter is a latch with the extra ability to incr

10、ement by 1 when told to do so, and also to reset to zero when told to do so.line changes state, the ROM chip presents the selected byte onto the data bus.RAM stands for random-access memory. RAM contains bytes of informa

11、tion, and the microprocessor can read or write to those bytes depending on whether the RD or WR line is signaled. One problem with today’s RAM chips is that they forget everything once the power goes off. That is why the

12、 computer needs ROM.By the way, nearly all computers contain some amount of ROM (it is possible to create a simple computer that contains no RAM—many microcontrollers do this by placing a handful of RAM bytes on the proc

13、essor chip itself—but generally impossible to create one that contains no ROM).On a PC, the ROM is called the BIOS (Basic Input/Output System). When the microprocessor starts, it begins executing instructions it finds in

14、 the BIOS. The BIOS instructions do things like test the hardware in the machine, and then it goes to the hard disk to fetch the boot sector. This boot sector is another small program, and the BIOS store it in RAM after

15、reading it off the disk. The microprocessor then begins executing the boot sector’s instructions from RAM. The boot sector program will tell the microprocessor to fetch something else from the hard disk into RAM, which t

16、he microprocessor then executes, and so on. This is how the microprocessor loads and executes entire operating system.Microprocessor Instructions Even the incredibly simple microprocessor shown here will have a fairly la

17、rge set of instructions that it can perform. The collection of instructions is implemented as bit patterns, each one of which has a different meaning when loaded into the instruction register. Humans are not particularly

18、 good at remembering bit patterns, so a set of short words are defined to represent the different bit patterns. This collection of words is called the assembly languages of the processor. An assembler can translate the w

19、ords into their bit patterns very easily, and then the output of assembler is placed in memory for the microprocessor to execute. If you use C language programming, a C compiler will translate the C code into assembly la

20、nguage.So now the question is, “How do all of these instructions look in ROM?” Each of these assembly language instructions must be represented by a binary number. These numbers all know as recodes. The instruction decod

21、er needs to turn each of recodes into a set of signals that drive the different components inside the microprocessor. Let’s take the ADD instruction as an example and look at what it needs to do.During the first clock cy

22、cle, we need to actually load the instruction. Therefore the instruction decoder needs to: activate the tri-state buffer for the program counter; activate the RD line; activate the data-in tri-state buffer; latch the ins

23、truction into the instruction register.During the second clock cycle, the ADD instruction is decoded. It needs to do very little: set the operation of ALU to addition; latch the output of the ALU into the C register.Duri

24、ng the third clock cycle, the program counter is incremented (in theory this could be overlapped into the second clock cycle).Every instruction can be broken down as a set of sequenced operations like these that manipula