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Lecture 1 - Introduction Instructor : Bibhas Ghoshal ([email protected]) Spring Semester, 2016 Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 1 / 21
Lecture 1 - Introduction
Instructor : Bibhas Ghoshal ([email protected])
Spring Semester, 2016
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 1 / 21
Lecture Outline
Objective of the courseDefining Computer Organization and Computer ArchitectureComputer System Structure and Function
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 2 / 21
Course Objective
Improvement in computer technology in terms of computational power,storage and cost is mainly due to :
advances in the technology used to build computersinnovation in computer design
Our objective in this course would be:To touch upon both architectural and organizational attributes of acomputer systemLearn how these attributes contribute to build a completecomputer systemWe will determine the attributes which are important for a newmachine, and then design a machine to maximize performancewhile staying within cost
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 3 / 21
Course Objectives
The course aims at exploring the knowledge of hardware support thatfacilitates efficient computing. The central ideas dicussed are :
Components of computer system - memory, datapath, control,input, and outputData - integers, floating point, characters, bitstream. The actualvalues and use of data are determined by the program (software)running on the computer.Stored program (Von Neuman) model - instructions and data arestored in memory. They can be accessed randomly orsequentially, and can be input or output (read or written in and out,respectively) to increase memory utilization.
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 4 / 21
Course Objectives
Design of a computer system - integrating the components to buida complete systemCache for performance enhancement - The phenomenon oflocality supports scheduling and prediction of memory accesses,which enables devices like caches to work efficiently.Pipeline and ParallelismPerformance of the computer system
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 5 / 21
Computer Architecture
Parameters of a computer system that are visible to aprogrammer, and that have a direct impact on the logicalexecution of a program.Examples : architectural attributes - instruction set, IOmechanisms, and techniques for addressing memory.
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 6 / 21
Computer Organization
Operational units and their interconnections that realize thearchitectural specifications.Examples : organizational attributes - hardware detailstransparent to the programmer, such as control signals, interfacesbetween the computer and peripherals, and the memorytechnology used.
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 7 / 21
Computer System
The computer system is described as a hierarchic system.A hierarchic system is a set of interrelated subsystems, each of latter,in turn, hierarchic in structure until we reach some lowest level ofelementary subsystem.
The designer need only deal with a particular level of the systemat a time.At each level, system consists of set of components and theirinterrelations.The behaviour at each stage depends on a simpified, abstractedcharacterization of the system at next lower level.At each level, the designer is concerned with structure andfunction
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 8 / 21
Computer Abstraction
Figure : Levels of abstraction in computer system
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 9 / 21
Computer Abstraction
Figure : Another view of Levels of abstraction in computer system
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 10 / 21
Computer Abstraction
Figure : Another view of Levels of abstraction in computer system
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 11 / 21
Computer System
Structure : The way in which components are interrelatedFunctions : The operation of each individual component as part ofthe structure
Functions:Data ProcessingData StorageData MovementControl
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 12 / 21
Computer System Structure
The model of a computer can be described by four basic units in highlevel abstraction. These are:
Central Processing UnitInput UnitOutput UnitMemory
CPU
Control
ALU
Memory I/O devices
Registers
Figure : Computer System
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 13 / 21
Computer System Structure
Figure : Computer System
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 14 / 21
Computer System
Central Processor Unit (CPU) :
Basic blocks of CPUThe program control unit has a set of registers and control circuitto generate control signals.The execution unit or data processing unit contains a set ofregisters for storing data and an Arithmetic and Logic Unit (ALU)for execution of arithmetic and logical operations.In addition, CPU may have some additional registers fortemporary storage of data.
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 15 / 21
Computer System
Central Processor Unit (CPU) :
Figure : Computer System
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 16 / 21
Computer SystemInput Unit
With the help of input unit data from outside can be supplied to thecomputer. Program or data is read into main storage from input deviceor secondary storage under the control of CPU input instruction.
Figure : Computer System
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 17 / 21
Computer SystemOutput Unit
With the help of output unit computer results can be provided to theuser or it can be stored in storage device permanently for future use.Output data from main storage go to output device under the control ofCPU output instructions.
Figure : Computer System
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 18 / 21
Computer SystemPrimary Memory
Memory unit is used to store the data and program. CPU can workwith the information stored in memory unit. This memory unit is termedas primary memory or main memory module. These are basically semiconductor memories.
Volatile Memory : RAM (Random Access Memory).Non-Volatile Memory : ROM (Read only Memory), PROM(Programmable ROM) EPROM (Erasable PROM), EEPROM(Electrically Erasable PROM).
Figure : Computer System
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 19 / 21
Computer SystemSecondary Memory
Secondary memories are non volatile memory and it is used forpermanent storage of data and program. Example of secondarymemories: Hard Disk, Floppy Disk, Magenetic Tape, CD-ROM, pendrive
Figure : Computer System
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 20 / 21
Instructing the Computer
Program Executable Outputcompile execute
Write a program in a high level language say in CCompile it into a format that the computer understandsThe compiled code is stored in memoryCPU fetches the compiled code sequentially from memory ito itsregistersexecutes the code using Arithmetic and Logic Unit on instructionsfrom the Control Unit
Bibhas Ghoshal ICOA230C: COA Spring Semester, 2016 21 / 21
