TFB1053_LCW01 - Intro to Comp Sys - for Lecture.pptx

TFB 1053 COMPUTER SYSTEMS   Fundamental of Computer Systems  Learning objectives  To describe basic Computer System components o Computer User o Computer Task o Data Processing  To differentiate between Computer Architecture and Comput...

TFB 1053 COMPUTER SYSTEMS   Fundamental of Computer Systems  Learning objectives  To describe basic Computer System components o Computer User o Computer Task o Data Processing  To differentiate between Computer Architecture and Computer Organisation  To describe history of Computer Systems Development Introduction: Why Study Computer Systems?  One of the largest and most complicated software system.  Draws on lots of areas: o Software engineering, computer architecture, data structure, networks, algorithms…  Can apply techniques used to other areas: o conflict resolution, concurrency, resource management and complex data structure Introduction: Why Study Computer Systems? pe Var  User rs iou pe cti s o Understand system capabilities and limitations ve s o Make informed decisions o Improve communications with information technology professionals  Systems Analyst o Conduct surveys, determine feasibility and define and document user requirements o Able to understand the technical specification o Specify computer systems to meet application requirements  Programmer o Create efficient application software for specific processing needs  Introduction: Why Study Computer Systems? pe Var  System Administrator / Manager rs iou pe cti s o Install, configure, maintain, and upgrade ve s computer systems o Maximize system availability o Optimize system performance o Ensure system security  Web Designer o Optimize customer accessibility to Web services o System administration of Web servers o Select appropriate data formats o Design efficient Web pages  Architecture vs. Organisation  Architecture is concerned by those attribute visible to the programmer (either at the higher or lower levels) o Instruction set (for CPU chips), data bits, address bits, I/O operations, memory and device addressing techniques. o Can we divide or multiply numbers with one instruction?  Organisation is how features are implemented o Control signals, interface, memory technology o Is there a hardware device that we can use to perform an arithmetic division or a multiplication in one go or can we only do so by repeated arithmetic addition  Architecture vs. Organisation  Intel X86-based family of computers share the same basic architecture. o Back-compatibility ensured. Program that run on Intel486 based computers, also run Intel386, Intel286 and Intel86 based computers  IBM System/370 family share same basic architecture o Back-compatibility ensured  Organisation may be different from one model to another or from one version to another  Input-Process-Output Model (IPO)  Input: keyboard, mouse, scanner, punch cards, Magnetic Tapes, Floppy Disks, Hard Disks, CD-ROMs, Card Reader (e.g. Credit Card, Smart Card, Touch Card,  Output: monitor, printer, fax Loyalty Card), machine, plotters, Magnetic Tapes, Network Devices Floppy Disks, Hard Disks, CD- Infra-red Readers RWs, Network Devices  Processing: CPU  Storage: hard drive, optical media, executes the diskettes, magnetic tape computer program Basic Data Processing: Data movement Operation  Input/Output  Data Transformation  Data Storage and or Translation (e.g. program compilation, file Retrieval updating)  Internet Downloads  Searching Data  Wireless Transmission Storage for Matches and Reception of Data  True/False Decision  Basic Arithmetic and Making and Branching Logical Operation (If…then…else)  Sorting Data  Loop and Repeated Tasks  An Example: An ATM Machine  ATM (Automatic Teller Machine) Operation: Input Retrieve Customer Keypad (Pin Number) Account Information Process (Check Transaction) Update Output Account (Screen Display) (Printing Receipt) Typical Personal Computer System Component of a Computer System The Hardware Component The Software Component The Data Component Computer System Components  Hardware o Processes data by executing instructions o Provides input and output  Software o Instructions executed by the system  Data o Fundamental representation of facts and observations o Eg Files, Databases and Hardcopy  Communications o Sharing data and processing among different systems o Eg: Network Connections, Protocol and Devices  Hardware Component  Input/Output devices - Physical devices used to input/output, and manipulate or process data  Storage Devices  Central Processing Unit (CPU) o ALU: arithmetic/logic unit o CU: control unit o Interface unit  Memory o Short-term storage for CPU calculations The CPU - Top Level View  CPU: Central Processing Unit  ALU: arithmetic/logic unit  IU: Interface Unit o Performs arithmetic o also known as Registers Unit and Boolean logical o Ensuring communication calculations e.g. between the CPU and the other multiplication, division components of the computer or comparison of such as memory and I/O numbers. peripheral devices. o Most computer o Moves instructions and data operation are executed between the CPU and other in ALU hardware components o Much faster than other  CU: Control Unit devices - enables a o Controls processing of single processor to instructions control a number of o Controls movement of data external devices such within the CPU as video terminal, o CU is a centre that sends magnetic tape, disk control signals to other units memory etc. and senses their states.  Memory  Also known as primary storage, working storage, and RAM (random access memory)  Consists of bits, each of which hold a value of either 0 or 1 (8 bits = 1 byte)  Holds both instructions and data of a computer program (stored program concept)  The main memory contains a large number of semiconductor storage cells, each capable of storing one bit of information  Memory  Memory is always measured in terms of Bytes, Kilobytes, Megabytes or Gigabytes. 1 Byte = 8 Bits 1KB(Kilobytes) = 1024 Bytes 1MB(Megabytes) = 1024 Kilobytes = 1048576 Bytes 1GB(Gigabytes) = 1024 Megabytes = 1073741824 Bytes 1TB(Terabytes) = 1024 Gigabytes  Size of the primary memory can help to determine: o The largest program (including its data) that can be loaded into a computer and executed in one go. o How fast a computer executes a program. o How much computer might cost.  Software Component  Programmable instruction that tell the hardware what to do and how to behave  System Software - (usually tight linked to the hardware and can be modified only by the manufacturer of the hardware, e.g. Operating System, Device Derives, etc). It is usually stored in Read Only Memory (ROM)  Application Software: High level programmers (using VB or C++ or Pascal or Delphi) write programmes that enhance and extend the functionality of a computer. (Ms Word, Netscape, Adobe Acrobat Reader, Lotus 1-2-3, etc)  Application Programmer’s Interface - API (A key for an end-user programmer to talk to the system software)  Communications Component  Hardware o Communication channels Physical connections between computer systems Examples: wire cable, phone lines, fiber optic cable, infrared light, radio waves o Interface hardware Handles communication between the computer and the communication channel Modem or network interface card (NIC)  Software o Network protocols: HTTP, TCP/IP, ATAPI  Computer Systems All computer systems, no matter how complex, consists of the following:  At least one CPU  Memory to hold programs and data  I/O devices  Long-term storage  Protocols  Common ground rules of communication between computers, I/O devices, and many software programs  Examples o HTTP: between Web servers and Web browsers o TCP/IP: between computers on the Internet and local area networks o ATAPI: between a CPU and CD-ROMs  Standards  Created to ensure universal compatibility of data formats and protocols  May be created by committee or may become a de facto standard through popular use  Examples: o Computer languages: Java, SQL, C, JavaScript o Display standards: Postscript, MPEG-2, JPEG, GIF o Character set standards: ASCII, Unicode, EBCDIC o Video standards: VGA, XGA, RGB  Early History  1642: Blaise Pascal invents a calculating machine  1801: Joseph Marie Jacquard invents a loom that uses punch cards  1800’s: o Charles Babbage attempts to build an analytical engine (mechanical computer) o Augusta Ada Byron develops many of the fundamental concepts of programming o George Boole invents Boolean logic.  Modern Computer Development  1937: Mark I is built (Aiken, Harvard University, IBM). o First electronic computer using relays.  1939: ABC is built o First fully electronic digital computer. Used vacuum tubes.  1943-46: ENIAC (Mauchly, Eckert, University of Pennsylvania). o First general purpose digital computer.  1945: Von Neumann architecture proposed. o Still the standard for present day computers.  1947: Creation of transistor o (Bardeen, Shockley, Brattain, Bell Labs).  1951: UNIVAC. o First commercially available computer.  Early Computers Babbage’s Analytical Engine ENIAC  Machine Hardware  Advances in computer technology o Dramatic changes in physical size, cost, and memory capacity o Networking is an integral part of modern computer systems o Delivering information to a mobile society, creating a strong market for handheld devices o Classified by processor capacity instead of memory capacity o Computing power rises exponentially — Moore’s Law  Summary  Architecture vs. Organisation  Basic Computer Task and Data Processing  Component of a Computer System  Input-Process-Output model  Demonstrated the connection between the model and the component of the computer system  The implementation of the model requires four components: hardware, software, communication and data