Hardware and Software

1
Hardware and Software

• Chapter 2

2
Learning Objectives

• Identify and discuss the role of the essential
  hardware components of a computer system.
• List and describe popular classes of computer
  systems and discuss the role of each.
• Outline the role of the operating system and
  discuss how operating systems have evolved over
  time.
• Identify and briefly describe the functions of
  the two basic kinds of software.

3
Computer System Components

Math calculations
Access, decode, coordinate instructions
Hold program instructions and data
4
Hardware Components in Action

• Instruction phase
• Step 1 Fetch instruction
• Step 2 Decode instruction
• Execution phase
• Step 3 Execute the instruction
• Step 4 Store the results

5
Execution of an Instruction
6
Processing and Memory Devices
7
Processing Characteristics and Functions

• Machine cycle time Time to execute the
  instruction phase
• Clock speed
• Rate at which electronic pulses are produces.
• Measured in MHz
• Wordlength
• Bit (Binary digiT) 0 or 1
• Unit for moving data
• Wordlength The number of bits a CPU can process
  in a unit time
• 32-64 bit processors

8
Moores Law

• Number of transistors doubles every 18 months

9
Number of Bytes

10
Types of Memory (1)

• Random access memory (RAM)
• Volatile
• Extended Data Out (EDO) RAM
• Dynamic Ram (DRAM)
• Synchronous DRAM
• Faster transfer speed between memory and
  processor

11
Types of Memory (2)

• Read-only memory (ROM)
• Non-volatile
• Permanent data and instructions from manufacturer
• Types
• PROM Programmable
• EPROM Erasable programmable

12
Basic Types of Memory Chips
13
Secondary Storage and Output Devices
14
Cost Comparisons for Various Forms of Data
Storage
15
Secondary Storage Access Methods

• Sequential access
• Access in the same order it was written
• Ex Need to access memory location 5. Then, you
  need to go through 1, 2, 3, and 4 first.
• Direct access
• Directly access the location
• Faster than sequential access
• Sequential access storage devices (SASD)
• Direct access storage devices (DASD)

16
Secondary Storage Devices (1)

• Magnetic tapes Similar to audio tapes, SASD
• Magnetic discs Hard disk, DASD
• RAID Redundant array of independent inexpensive
  disks
• Data stored more than once in one of the disks
• Even if one disk fails, data can still be
  retrieved
• SAN Storage area network
• Consist of many storage devices
• Optical discs, DASD
• CD-ROM

17
Secondary Storage Devices (2)

• Magneto-optical discs
• Digital versatile discs (DVD) Up to 17 GB
  storage
• Memory cards
• Installed in a slot
• Portable
• Expandable storage Removable disk cartridges
• Portable
• Zip drives

18
Types of Secondary Storage
19
Hard Disc
20
Storage Area Network
21
Digital Versatile Disc Player
22
Expandable Storage
23
Comparison of Secondary Storage Devices
24
Input Devices

• Personal computer input devices
• Keyboard
• Mouse
• Voice-recognition devices
• Microphone
• Software to convert voice into bits
• Digital computer cameras
• Record images and video
• Terminals
• Connects to a powerful server for computations
• Scanning devices
• Page
• Handheld
• Touch-sensitive Screens

25
A PC Equipped with a Computer Camera
26
Output Devices

• Display Monitors
• Cathode Ray Tube (CRT)
• Wide
• Lights up pixels
• Liquid Crystal Displays (LCDs)
• Flat panel
• Printers and Plotters
• Speed measured in pages (page printed per minute)
• Music Devices
• MP3 Players

27
Laser Printer
28
Types of Computer Systems
29
Overview of Software
30
Overview of Software

• Computer programs Sequences of instructions
• Documentation Describe program functions
• Systems software Coordinate the activities of
  the hardware
• Computer system platform
• Hardware configuration systems software
• Application software Programs that help users
  with certain tasks

31
Classifying Software by Type and Sphere of
Influence
32
Systems Software
33
Operating Systems

• Perform common computer hardware functions
• Ex Get input from keyboard
• Provide a user interface
• Command-based user interface (ms-dos)
• Graphical-user interface (windows)
• Provide a degree of hardware independence
• Application program interface
• Manage system memory
• Convert logical view to physical view

34
Operating Systems

• Manage processing tasks
• Allocate computer resources
• Multitasking (run more than once application at a
  time)
• Time-sharing (allow multiple access to a system)
• Provide networking capability
• Enable connection to the Internet
• Control access to system resources
• Authentication
• Manage files
• Access to files

35
Role of the Operating System
36
Application Program Interface
37
An Example of the Operating System Controlling
Physical Access to Data
38
Popular Operating Systems
39
Workgroup Operating Systems

• Windows 2000 Server
• Unix
• Netware
• Red Hat Linux
• Mac OS X Server

40
Consumer Appliance Operating Systems

• Windows CE .NET
• Windows XP Embedded
• Handheld PC
• Pocket PC
• Palm OS

41
Application Software
42
Sources of Software
43
Proprietary and Off-the-Shelf Software
44
Examples of Personal Productivity Software
45
TurboTax
46
Quicken
47
Word Processing Program
48
Spreadsheet Program
49
Database Program
50
Graphics Program
51
Software Suites
52
Enterprise Application Software
53
Use of Integrated Supply Chain Management
Software
54
Selected Enterprise Resource Planning Vendors
55
Summary of Programming Languages

• First Computer interactions written in machine
  code
• Machine language
• Second
• Abbreviations for common operations
• Assembler converts code to machine language
• Assembly language
• Third
• Instructions are English-like
• Compliers convert code to machine language
• Fortran Good for scientific computing
• Cobol Good file handling
• Java Good for Web applications

56
Summary of Programming Languages

• Fourth
• Even easy for non-programmers
• Tell what to do, not how to do it
• Focus, Powerhouse
• Visual Programming Languages
• Point-and-click
• Drag-and-drop
• Useful for user interfaces
• Visual Basic, Visual C
• Object-oriented Languages
• Objects contain data, methods to operate data
• C, Java

57
Summary

• Hardware devices work together to perform input,
  processing, data storage, and output.
• There are two main categories of software
  systems software and application software.
• An operating system (OS) is a set of computer
  programs that controls the computer hardware to
  support users computing needs.
• Application software may be proprietary or
  off-the-shelf.
• There are five generations of programming
  languages, plus object-oriented programming
  languages.