6. COMPUTERS

1
6. COMPUTERS AND INFORMATION PROCESSING
6.1
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LEARNING OBJECTIVES

• IDENTIFY HARDWARE COMPONENTS
• DESCRIBE HOW DATA IS REPRESENTED
• CONTRAST MAINFRAMES, MINICOMPUTERS,
  SUPERCOMPUTERS, PCs, WORKSTATIONS

6.2
3
LEARNING OBJECTIVES

• COMPARE ARRANGEMENTS OF COMPUTER PROCESSING
  CLIENT/SERVER, NETWORK
• DESCRIBE MEDIA FOR STORING DATA
• COMPARE INPUT/OUTPUT DEVICES
• DESCRIBE MULTIMEDIA, TRENDS

6.3
4
MANAGEMENT CHALLENGES

• WHAT IS A COMPUTER SYSTEM?
• CPU AND PRIMARY STORAGE
• COMPUTERS COMPUTER TECHNOLOGIES
• SECONDARY STORAGE
• INPUT OUTPUT DEVICES
• INFO TECHNOLOGY TRENDS

6.4
5
COMPUTER COMPONENTS
BUSES
6.5
6
HOW CHARACTERS ARE STORED

• BIT Binary Digit. On/Off, 0/1, Magnetic/Not
• BYTE Group of bits for one character
• EBCDIC- Extended Binary Coded Decimal Interchange
  Code (8 bits per byte)
• ASCII- American Standard Code for Information
  Exchange (7 or 8 bits per byte)
• PARITY BIT extra bit added to each byte to help
  detect errors

6.6
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EXAMPLES OF BYTES
EBCDIC ASCII (assume
even-parity system)

• C 1100 0011 0 100 0011 1
• A 1100 0001 1 100 0001 0
• T 1110 0011 1 101 0100 1
• Note how sum for each byte is an EVEN
  number

6.7
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COMPUTER TIME
PER COMPARED
NAME LENGTH
SECOND TO 1 SECOND

• Millisecond .001 second thousand
  15min 40 sec
• Microsecond .001 millisecond million
  11.6 days
• Nanosecond .001microsecond billion
  31.7 years
• Picosecond .001 nanosecond trillion
  31,700 years

6.8
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MEMORY SIZE

• KILOBYTE (KT) 210 bytes... 1024 bytes
• MEGABYTE (MB) 210 KB... million bytes
• GIGABYTE (GB) 210 MB... billion bytes
• TERABYTE (TB) 210 GB... trillion bytes

6.9
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COMPUTER GENERATIONS

• 1. VACUUM TUBES 1946-1956

6.10
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COMPUTER GENERATIONS

• 1. VACUUM TUBES 1946-1956
• 2. TRANSISTORS 1957-1963

6.11
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COMPUTER GENERATIONS

• 1. VACUUM TUBES 1946-1956
• 2. TRANSISTORS 1957-1963
• 3. INTEGRATED CIRCUITS 1964-1979

6.12
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COMPUTER GENERATIONS

• 1. VACUUM TUBES 1946-1956
• 2. TRANSISTORS 1957-1963
• 3. INTEGRATED CIRCUITS 1964-1979
• 4. VERY LARGE-SCALE INTEGRATED (VLSI) CIRCUITS
  1980- PRESENT

6.13
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CENTRAL PROCESSING UNIT (CPU)
CONTROL UNIT
6.14
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BUSES
DATA BUS ADDRESS BUS CONTROL BUS
6.15
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TYPES OF MEMORY

• RAM Random Access Memory
• Dynamic Changes thru processing
• Static Remains constant (power on)
• ROM Read Only Memory (preprogrammed)
• PROM Program can be changed once
• EPROM Erasable thru ultraviolet light
• EEPROM Electrically erasable

6.16
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ADDRESSES IN MEMORY
Each location has an ADDRESS
Each location can hold one BYTE
6.17
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ALU CONTROL UNIT

• ARITHMETIC- LOGIC UNIT CPU component performs
  logic and arithmetic operations
• CONTROL UNIT CPU component controls, coordinates
  other parts of computer system

6.18
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INSTRUCTION EXECUTION CYCLE

• I-CYCLE
• 1. FETCH
• 2. DECODE
• 3. PLACE IN INSTRUCTION REGISTER
• 4. PLACE INTO ADDRESS REGISTER

6.19
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INSTRUCTION EXECUTION CYCLE

• E-CYCLE
• 5. SEND DATA FROM MAIN MEMORY TO STORAGE
  REGISTER
• 6. COMMAND ALU
• 7. ALU PERFORMS OPERATION
• 8. SEND RESULT TO ACCUMULATOR

6.20
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CATEGORIES OF COMPUTERS

• MAINFRAME
• MINICOMPUTER
• PERSONAL COMPUTER (PC)
• WORKSTATION
• SUPERCOMPUTER

6.21
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MAINFRAME
MIPS Millions of Instructions per second

• LARGEST ENTERPRISE COMPUTER
• 5O MEGABYTES TO OVER ONE GIGABYTE RAM
• COMMERCIAL, SCIENTIFIC, MILITARY APPLICATIONS
• MASSIVE DATA
• COMPLICATED COMPUTATIONS

6.22
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MINICOMPUTER

• MIDDLE-RANGE
• 10 MEGABYTES TO OVER ONE GIGABYTE RAM
• UNIVERSITIES, FACTORIES, LABS
• USED AS FRONT-END PROCESSOR FOR MAINFRAME

6.23
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MICROCOMPUTER

• DESKTOP OR PORTABLE
• 64 KILOBYTES TO OVER 128 MEGABYTES RAM
• PERSONAL OR BUSINESS COMPUTERS
• AFFORDABLE
• MANY AVAILABLE COMPONENTS
• CAN BE NETWORKED

6.24
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WORKSTATION

• DESKTOP COMPUTER
• POWERFUL GRAPHICS
• EXTENSIVE MATH CAPABILITIES
• MULTI-TASKING
• USUALLY CONFIGURED TO SPECIAL FUNCTION (e.g.
  CAD, ENGINEERING, GRAPHICS)

6.25
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SUPERCOMPUTERTERAFLOP TRILLION
CALCULATIONS/SECOND

• HIGHLY SOPHISTICATED
• COMPLEX COMPUTATIONS
• FASTEST CPUs
• LARGE SIMULATIONS
• STATE-OF-THE-ART COMPONENTS
• EXPENSIVE

6.26
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SEQUENTIAL PARALLEL PROCESSING
SEQUENTIAL
PARALLEL
6.27
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MICROPROCESSOR

• VLSI CIRCUIT WITH CPU
• WORD LENGTH bits processed at one time
• MEGAHERTZ one million cycles per second
• DATA BUS WIDTH bits moved between CPU other
  devices
• REDUCED INSTRUCTION SET COMPUTING (RISC) embeds
  most used instructions on chip to enhance speed
• MultiMedia eXtension (MMX) enhanced Intel chip
  improves multimedia applications

6.28
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EXAMPLES OF MICROPROCESSORS
6.29
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USES OF MICROPROCESSORS
6.30
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CENTRALIZED / DISTRIBUTED

• CENTRALIZED PROCESSING BY CENTRAL COMPUTER SITE
• ONE STANDARD
• GREATER CONTROL
• DISTRIBUTED PROCESSING BY SEVERAL COMPUTER SITES
  LINKED BY NETWORKS
• MORE FLEXIBILITY
• FASTER RESPONSE

6.31
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CLIENT / SERVER

• NETWORKED COMPUTERS
• CLIENT user (PC, workstation, laptop) requires
  data, application, communications it does not
  have
• SERVER component (computer) having desired data,
  application, communications

6.32
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CLIENT / SERVER
CLIENT SERVER
USER INTERFACE APPLICATION FUNCTION
DATA APPLICATION FUNCTION NETWORK RESOURCES
6.33
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DOWNSIZING

• TRANSFER APPLICATIONS FROM LARGE COMPUTERS TO
  SMALL
• REDUCES COST
• SPEEDS RESULTS TO USER
• COMPUTER ASSIGNED TASK IT DOES BEST
• COOPERATIVE PROCESSING

6.34
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NETWORK COMPUTERS

• NETWORK COMPUTER simplified desktop computer
  stores minimum data to function (uses server)
• TOTAL COST OF OWNERSHIP (TCO) total cost of
  owning technology resources (hardware, software,
  upgrades, maintenance, technical support,
  training)

6.35
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SECONDARY STORAGE

• DISK
• TAPE
• OPTICAL STORAGE

6.36
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DIRECT ACCESS STORAGE DEVICE

• HARD DISK Steel platter array for large computer
  systems
• RAID Redundant array of Inexpensive Disks
• FLOPPY DISK Removable disk for PC

6.37
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DISK PACK STORAGE

• LARGE SYSTEMS
• RELIABLE STORAGE
• LARGE AMOUNTS OF DATA
• QUICK ACCESS RETRIEVABLE
• TYPICAL 11 2-SIDED DISKS
• CYLINDER SAME TRACK ALL SURFACES

6.38
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TRACKS AND SECTORS
EACH TRACK HOLDS SAME AMOUNT OF DATA
SECTOR
6.39
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OPTICAL STORAGE

• CD-ROM 500-660 MEGABYTES
• LAND flat parts of disk surface reflects light
• PITS small scratch on surface scatters light
• WRITE ONCE / READ MANY (WORM)
• CD-R Compact Disk - Recordable
• CD-RW CD - Rewritable
• DIGITAL VIDEO DISK (DVD) CD size, up to 10
  gigabytes of data

6.40
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MAGNETIC TAPE

• STANDARD FOR SEQUENTIAL FILES
• SPOOL OF PLASTIC TAPE COVERED WITH FERROUS OXIDE
  (2400 feet per spool)
• RECORD GROUPS BLOCKING FACTOR (e.g., 10 records
  per block)
• GROUPS SEPARATED BY INTER-BLOCK GAP
• RECORDS READ BLOCK AT A TIME

HEADER IBG BLOCK 1 BLOCK 2
BLOCK 3
6.41
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MAGNETIC CARTRIDGE

• ENCLOSED FERROUS OXIDE TAPE
• USED PERIODICALLY TO BACK UP RECORDS
• INEXPENSIVE
• STORED IN SAFE LOCATION
• CAN BE REUSED

6.42
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PERIPHERAL DEVICES

• POINTING DEVICES
• SOURCE DATA AUTOMATION
• OUTPUT DEVICES

6.43
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POINTING DEVICES

• KEYBOARD
• MOUSE
• WIRED
• INFRA-RED
• TRACKBALL
• TOUCH PAD
• JOYSTICK
• TOUCH SCREEN

6.44
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SOURCE DATA AUTOMATION

• CAPTURES DATA IN COMPUTER FORM AT TIME PLACE OF
  TRANSACTION
• OPTICAL CHARACTER RECOGNITION (OCR) saves
  characters, format
• BAR CODE identifies products in stores,
  warehouses, shipments
• MAGNETIC INK CHARACTER RECOGNITION (MICR)
  special ink identifies bank, account, amount

6.45
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SOURCE DATA AUTOMATION

• PEN-BASED INPUT digitizes signature
• DIGITAL SCANNER translates images characters
  into digital form
• VOICE INPUT DEVICES converts spoken word into
  digital form
• SENSORS devices that collect data from
  environment for computer input (e.g.,
  thermometers, pressure gauges)

6.46
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OUTPUT DEVICES

• CATHODE RAY TUBE (CRT)
• PRINTER
• PLOTTER
• VOICE OUTPUT DEVICE
• MULTIMEDIA

6.47
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DATA PROCESSING

• BATCH PROCESSING transaction data stored until
  convenient to process as a group. Useful for less
  time-sensitive actions.
• ON-LINE PROCESSING transaction data entered
  directly into system, constantly updating files.
  Requires direct-access devices.

6.48
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BATCH PROCESSING
6.50
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ON-LINE PROCESSING
6.50
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TECHNOLOGY TRENDS

• INTERACTIVE MULTIMEDIA
• VIRTUAL REALITY
• ENHANCED WORLD WIDE WEB
• SUPERCHIPS
• FIFTH GENERATION COMPUTERS
• MASSIVELY PARALLEL COMPUTERS
• SMART CARDS
• MICROMINIATURIZATION

6.51
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PRESS LEFT MOUSE BUTTON ON ICON TO CONNECT TO THE
LAUDON LAUDON WEB SITE FOR MORE INFORMATION ON
THIS CHAPTER
6.52
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6. COMPUTERS AND INFORMATION PROCESSING
6.53