Chapter 1

Introduction

Objectives

• To explain the definition of computer architecture

• To discuss the history of computers

• To describe the von-neumann machine architecture

• To discuss how to measure the quality of a computer architecture and the factors that influence the success of a computer architecture

• To introduce the concept of computer as a hierarchical system using structure and functions

• To describe the functions of each component in a computer

Organization and architecture• Architecture -- refers to those attributes of a system visible

to a programmer or those attributes that have a direct impact on the logical execution of a program.

- instruction set, number of bits used for data

representation, I/O mechanism, addressing technique.

• Organization – refers to the operational unit and their

interconnections that realize the architectural specification

-- control signal, interface to peripherals, memory

technology.

4

Computer Architecture

Computer Architecture

Instruction set designComputer InterfaceCompiler/System View

Machine OrganizationHardware componentsLogic Designer’s View

What is a computer?

• A computer is a tool for solving problems

(ex: perform arithmetic calculations)

• Requirements of a computer– process, store, moves, control

• 4 main functions performed by a computer– accepts ->process-> stores->produces

Computer Architecture

• Hayes: “The study of the structure, behavior and design of computers”

• Abd-Alla: “The design of the system specification at a general or subsystem level”

• Hennessy and Patterson: “The interface between the hardware and the lowest level software”

• :. the design of the computer at the hardware or software interface.

Structure and function

• Structure – The way in which the components relate to each other. E.g. connection between ALU and control unit, connection between Instruction register and instruction decoder.

• Function – The operation of each individual component as part of structure. E.g. How the ALU, Instruction register and instruction decoder work.

Function

These are the basic functions that a computer can perform.- Data processing- Data storage- Data movement- Control

Cont..• Process data – data can be a variety of forms, and the

range of processing requirements is broad. There are only a few fundamental methods of data processing ( refer ALU ).

• Store data – computer must temporarily store at least those pieces of data that are being worked on at any given moment at least a short-term data storage function (temporary register) and also long-term data storage function (store File).

• Move data – comp must be able to move data between itself and outside world. Device directly connected to computer is called peripheral. If data are moved over longer distances, the process is known data communication.

• Control – Control of three function above, and given by individuals who provides the computer with instruction.

Figure below depicts the four possible types of operations.

StructureThere are four main components in a computer structure:

- Central processing unit(CPU) – controls the operation of the computer and performs its data processing functions.

- Main memory – stores data- I/O – moves data between the computer and its external

environment- System interconnection – some mechanism that

provides for communication among CPU, main memory and I/O.

Traditionally a computer consist of single CPU, but in recent years, there has been increasing use of multiple processors in single computer.

The computer: Top-Level structure

The central processing unit

Control unit – controls the operation of the CPU and hence the computer.

ALU – perform data processing function

Register – provides storage internal to CPU

CPU interconnection – mechanism provides communication among the control unit, ALU and register.

14

Computer Structure

• Level one: The computer is device that can communicate with the outside world, and store and manipulate data.– The box, which can connect to networks (communication)

and peripherals (I/O)

– Software: operating system and applications

Computer Structure

• Level two: The computer has four component parts,– CPU (Central Processing Unit)

– Main Memory (RAM: Random Access Memory)

– I/O (Input/Output)

– System Interconnection (buses)

Computer Structure

• Level three: The CPU has four components– Arithmetic Logic Unit (ALU)

– Floating Point Unit (FPU)

– Registers (Data, Instruction, Stack, Integer, Floating Point)

– Control Unit

– Internal CPU connections (wires)

Computer Structure

• Level four: The control unit has three internal components– Sequencing logic

– Control unit registers and decoders

– Control memory

Any Question !!!!!!

OR

Quiz !!!

Sketch the internal connection of a Simple CPU

and explain in detail how it works

What are the differences between single core

technology and multi core technology.

Give 10 advantages of 8 bit processor and 64

bit processor.