6 1 LEARNING OBJECTIVES IDENTIFY HARDWARE COMPONENTS DESCRIBE
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LEARNING OBJECTIVES • IDENTIFY HARDWARE COMPONENTS • DESCRIBE HOW DATA IS REPRESENTED • CONTRAST MAINFRAMES, MINICOMPUTERS, SUPERCOMPUTERS, PCs, WORKSTATIONS 6. 2 *
LEARNING OBJECTIVES • COMPARE ARRANGEMENTS OF COMPUTER PROCESSING: CLIENT/SERVER, NETWORK • DESCRIBE MEDIA FOR STORING DATA • COMPARE INPUT/OUTPUT DEVICES • DESCRIBE MULTIMEDIA, TRENDS * 6. 3
MANAGEMENT CHALLENGES • • • WHAT IS A COMPUTER SYSTEM? CPU AND PRIMARY STORAGE COMPUTERS & COMPUTER TECHNOLOGIES • SECONDARY STORAGE • INPUT & OUTPUT DEVICES • INFO TECHNOLOGY TRENDS * 6. 4
COMPUTER COMPONENTS CPU INPUT DE VICES SECONDARY STORAGE BUSES OUTPUT DEVICES 6. 5 COMMUNICATIONS DEVICES PRIMARY STORAGE
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
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
COMPUTER TIME NAME Millisecond LENGTH . 001 second COMPARED TO 1 SECOND thousand 15 min 40 sec Microsecond. 001 millisecond million 11. 6 days Nanosecond. 001 microsecond billion 31. 7 years Picosecond trillion 31, 700 years . 001 nanosecond * 6. 8 # PER SECOND
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
COMPUTER GENERATIONS 1. VACUUM TUBES: 1946 -1956 6. 10
COMPUTER GENERATIONS 1. VACUUM TUBES: 1946 -1956 2. TRANSISTORS: 1957 -1963 6. 11
COMPUTER GENERATIONS 1. VACUUM TUBES: 1946 -1956 2. TRANSISTORS: 1957 -1963 3. INTEGRATED CIRCUITS: 1964 -1979 6. 12
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
CENTRAL PROCESSING UNIT (CPU) CONTROL UNIT ROM ARITHMETIC/LOGIC UNIT CLOCK PRIMARY (MAIN) MEMORY 6. 14 RAM
BUSES PRIMARY CPU STORAGE DATA BUS ADDRESS BUS CONTROL BUS 6. 15 INPUT OUTPUT SECONDARY DEVICES STORAGE
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
ADDRESSES IN MEMORY Each location has an ADDRESS Each location can hold one BYTE 6. 17 101 102 103 201 202 203 301 302 303
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
INSTRUCTION & EXECUTION CYCLE I-CYCLE: 1. FETCH 2. DECODE 3. PLACE IN INSTRUCTION REGISTER 4. PLACE INTO ADDRESS REGISTER * 6. 19
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
CATEGORIES OF COMPUTERS • • • MAINFRAME MINICOMPUTER PERSONAL COMPUTER (PC) WORKSTATION SUPERCOMPUTER * 6. 21
MAINFRAME MIPS: Millions of Instructions per second • LARGEST ENTERPRISE COMPUTER • 5 O MEGABYTES TO OVER ONE GIGABYTE RAM • COMMERCIAL, SCIENTIFIC, MILITARY APPLICATIONS • MASSIVE DATA • COMPLICATED COMPUTATIONS * 6. 22
MINICOMPUTER • MIDDLE-RANGE • 10 MEGABYTES TO OVER ONE GIGABYTE RAM • UNIVERSITIES, FACTORIES, LABS • USED AS FRONT-END PROCESSOR FOR MAINFRAME * 6. 23
MICROCOMPUTER • DESKTOP OR PORTABLE • 64 KILOBYTES TO OVER 128 MEGABYTES RAM • PERSONAL OR BUSINESS COMPUTERS • AFFORDABLE • MANY AVAILABLE COMPONENTS • CAN BE NETWORKED 6. 24 *
WORKSTATION • • • DESKTOP COMPUTER POWERFUL GRAPHICS EXTENSIVE MATH CAPABILITIES MULTI-TASKING USUALLY CONFIGURED TO SPECIAL FUNCTION (e. g. ; CAD, ENGINEERING, GRAPHICS) * 6. 25
SUPERCOMPUTER TERAFLOP: TRILLION CALCULATIONS/SECOND • • • HIGHLY SOPHISTICATED COMPLEX COMPUTATIONS FASTEST CPUs LARGE SIMULATIONS STATE-OF-THE-ART COMPONENTS EXPENSIVE * 6. 26
SEQUENTIAL & PARALLEL PROCESSING SEQUENTIAL PARALLEL Program TASK 1 CPU CPU TASK 1 TASK 2 TASK 3 RESULT Program TASK 2 CPU 6. 27 RESULT
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 • Multi. Media e. Xtension (MMX): enhanced Intel chip improves multimedia applications * 6. 28
EXAMPLES OF MICROPROCESSORS 6. 29
USES OF MICROPROCESSORS NAME 80486 PCs 68040 MAC QUADRAS PENTIUM PCs PENTIUM PRO PCs PENTIUM (MMX) MULTIMEDIA PENTIUM II HIGH-END PCs, WORKSTATIONS Power. PC HIGH-END PCs, WORKSTATIONS ALPHA PENTIUM III 6. 30 USE COMPAC & DEC WORKSTATIONS MULTIMEDIA
CENTRALIZED / DISTRIBUTED • CENTRALIZED: PROCESSING BY CENTRAL COMPUTER SITE – ONE STANDARD – GREATER CONTROL • DISTRIBUTED: PROCESSING BY SEVERAL COMPUTER SITES LINKED BY NETWORKS – MORE FLEXIBILITY 6. 31– FASTER RESPONSE
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
CLIENT / SERVER CLIENT REQUESTS SERVER DATA, SERVICE 6. 33 USER INTERFACE DATA APPLICATION FUNCTION NETWORK RESOURCES
DOWNSIZING TRANSFER APPLICATIONS FROM LARGE COMPUTERS TO SMALL • REDUCES COST • SPEEDS RESULTS TO USER • COMPUTER ASSIGNED TASK IT DOES BEST • COOPERATIVE PROCESSING * 6. 34
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 *
SECONDARY STORAGE • DISK • TAPE • OPTICAL STORAGE * 6. 36
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
DISK PACK STORAGE • • • LARGE SYSTEMS RELIABLE STORAGE LARGE AMOUNTS OF DATA QUICK ACCESS & RETRIEVABLE TYPICAL: 11 2 -SIDED DISKS CYLINDER: SAME TRACK ALL SURFACES READ/WRITE HEADS DISK 1 DISK 2 DISK 3 DISK 4 DISK 5 CYLINDER 10: TRACK 10 (TOP AND BOTTOM OF EACH DISK) 6. 38
TRACKS AND SECTORS TRACKS EACH TRACK HOLDS SAME AMOUNT OF DATA START OF TRACKS SECTOR 6. 39 DIRECTORY ON TRACK 0
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 *
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 6. 41 IBG BLOCK 1 BLOCK 2 BLOCK 3
MAGNETIC CARTRIDGE • ENCLOSED FERROUS OXIDE TAPE • USED PERIODICALLY TO BACK UP RECORDS • INEXPENSIVE • STORED IN SAFE LOCATION • CAN BE REUSED * 6. 42
PERIPHERAL DEVICES • POINTING DEVICES • SOURCE DATA AUTOMATION • OUTPUT DEVICES * 6. 43
POINTING DEVICES • KEYBOARD • MOUSE – WIRED – INFRA-RED – TRACKBALL – TOUCH PAD • JOYSTICK • TOUCH SCREEN 6. 44 *
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 *
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
OUTPUT DEVICES • • • CATHODE RAY TUBE (CRT) PRINTER PLOTTER VOICE OUTPUT DEVICE MULTIMEDIA * 6. 47
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 *
BATCH PROCESSING BATCH OF TRANSACTIONS KEYBOARD INPUT SORTED TRANSACTION FILE OLD MASTER FILE VALIDATE AND UPDATE ERROR REPORTS 6. 50 NEW MASTER FILE REPORTS
ON-LINE PROCESSING TRANSACTIONS KEYBOARD IMMEDIATE INPUT 6. 50 PROCESS / UPDATE MASTER FILE IMMEDIATE PROCESSING MASTER FILE IMMEDIATE FILE UPDATE
TECHNOLOGY TRENDS • • INTERACTIVE MULTIMEDIA VIRTUAL REALITY ENHANCED WORLD WIDE WEB SUPERCHIPS FIFTH GENERATION COMPUTERS MASSIVELY PARALLEL COMPUTERS SMART CARDS MICROMINIATURIZATION 6. 51 *
Connect to the INTERNET 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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