Ch6

Chapter 6AChapter 6ATransforming Data Into

Information

How Computers Represent How Computers Represent DataData

5A-2

How Computers Process How Computers Process DataData

Outline:Outline:

Components affecting SpeedComponents affecting Speed

How Computers Represent How Computers Represent DataDataNumber systems

◦A manner of counting◦Number systems have

Decimal number(0,1,2,………9)Binary number(0.1)

Decimal number system◦Used by humans to count◦Contains ten distinct digits◦Digits combine to make larger

numbers5A-3


5A-4

How Computers Represent How Computers Represent DataDataBinary number system

◦Used by computers to count◦Two distinct digits, 0 and 1◦0 and 1 combine to make numbers◦Example:◦0110 0001 = a

5A-5

How Computers Represent How Computers Represent DataDataBits and bytes

◦Binary numbers are made of bits◦Bit represents a switch◦A byte is 8 bits◦Byte represents one character.◦A=1 Byte and so on…

5A-6


Text codes Converts letters into binary. Standard codes necessary for data

transfer◦ASCII

American English symbols

◦Extended ASCII Graphics and other symbols

◦Unicode• provide enough characters to cover all the

world’s languages. 5A-7


5A-8

Examples from theASCII Text Code

How Computers Represent How Computers Represent DataDataWhy is it important to have a

standard text code?This standard code system would

enable any programmer or program to use the same combinations of numbers to represent the same individual pieces of data.

5A-9


5A-10

How Computers Process How Computers Process DataData1. The CPU

◦Central Processing Unit◦Brain of the computer◦Two part:1.Control unit

Controls resources in computer Contains the list of all commands a CPU

understands.2.Arithmetic logic unit (ALU)

I. Arithmetic operationsII.Logical operations Simple math operations Require Registers to store math operations

5A-11


5A-12


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How Computers Process How Computers Process DataDataMachine cyclesThe CPU follows a set of steps-called a

machine cycle to process data1.Instruction cycle

CPU gets the instruction

2.Execution cycle CPU performs the instruction

◦ Billions of cycles per second◦ Pipelining processes more data

5A-14

How Computers Process How Computers Process DataData2. Memory

◦Stores open programs and data◦Small chips on the motherboard◦More memory makes a computer

faster

5A-15

How Computers Process How Computers Process DataData3. Nonvolatile memory

◦Holds data when power is off◦Read Only Memory (ROM)

Store the routines that enable a computer to boot up

5A-16

How Computers Process How Computers Process DataData4. Flash memory• Data is stored using physical

◦Special form of nonvolatile memory◦Camera cards, USB

5A-17

How Computers Process How Computers Process DataData5. Volatile memory

◦Requires power to hold data◦Random Access Memory (RAM)◦Data in RAM has an address◦CPU reads data using the address

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Components affecting SpeedComponents affecting Speed

Affecting Processing Affecting Processing SpeedSpeed1. Registers

◦Number of bits processor can handle◦Larger indicates more powerful

computer◦Increase by purchasing new CPU

2. Virtual RAM◦Computer is out of actual RAM◦File that emulates RAM◦Computer swaps data to virtual RAM

Least recently used data is moved5A-20

Affecting Processing Affecting Processing SpeedSpeed3. The computer’s internal clock

◦Every tick causes a cycle◦Speeds measured in Hertz (Hz)

4. The bus◦Electronic pathway between

components◦System bus connects CPU and RAM◦Bus width is measured in bits

5A-21

Affecting Processing Affecting Processing SpeedSpeedExternal bus standards

1. Peripheral Control Interface(PCI)2. Accelerated Graphics Port(AGP)3. Universal Serial Bus(USB)4. PC Card

5A-22

Affecting Processing Affecting Processing SpeedSpeedPeripheral control interface (PCI)

◦Connects modems and sound cards

Accelerated Graphics Port (AGP)◦Connects video card to motherboard

5A-23

Affecting Processing Affecting Processing SpeedSpeedUniversal Serial Bus (USB)

◦Connects external devices◦Hot swappable◦Cameras, printers, and scanners

PC Card◦Used on laptops ◦Hot swappable◦Devices are the size of a credit card◦

5A-24

Affecting Processing Affecting Processing SpeedSpeed5. Cache memory

◦Very fast memory◦Holds common or recently used data◦Speeds up computer processing◦Most computers have several caches

5A-25

Modern CPUsModern CPUsChapter 6BChapter 6B

A Look Inside The ProcessorA Look Inside The Processor

5A-27

Comparing ProcessorsComparing Processors

Outline:Outline:

Extending The Processors PowerExtending The Processors Power

Microcomputer ProcessorsMicrocomputer Processors

A Look Inside The A Look Inside The ProcessorProcessorArchitecture

◦Determines Location of CPU parts Bit size Number of registers Pipelines

◦Main difference between CPUs

5B-28


1. Intel◦ Leading manufacturer of

processors◦ Current processors

Centrino Itanium Pentium IV Xeon

5B-29


2. Advanced Micro Devices (AMD)◦ Main competitor to Intel◦ Current processors

Sempron Athlon FX 64 Athlon XP

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3. Freescale◦ Currently focuses on the Linux

market

4. IBM◦ Historically manufactured

mainframes

Comparing ProcessorsComparing ProcessorsSpeed of processorSize of cacheNumber of registersBit sizeSpeed of Front side bus

Advanced Processor Advanced Processor TopicsTopicsParallel Processing

◦Multiple processors in a system

Extending The Processors Extending The Processors PowerPowerStandard computer ports

◦Keyboard and mouse ports◦USB ports◦Parallel◦Network◦Modem◦Audio◦Serial◦Video

5B-34

Standard computer portsStandard computer ports

◦Keyboard and mouse ports

◦USB ports


◦Parallel

◦Serial


Video

Audio


◦ Network & Modem Port

Standard Computer PortsStandard Computer Ports

5B-39

Extending The Processors Extending The Processors PowerPower

Serial and parallel ports◦Connect to printers or modems◦Parallel ports move bits

simultaneously◦Serial ports move one bit

5B-40

Serial CommunicationsSerial Communications

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Parallel CommunicationsParallel Communications

5B-42

Extending The Processors Extending The Processors PowerPowerSpecialized Expansion Ports:

USB◦Universal Serial Bus◦Most popular external bus◦Supports up to 127 devices◦Hot swappable

5B-43

Extending the Processors Extending the Processors PowerPowerFireWire

◦Cameras and video equipment◦Hot swappable

5B-44

Extending the Processors Extending the Processors PowerPowerExpansion slots and boards

◦Slots allow the addition of new devices

◦Computer must be off before inserting

5B-45

Extending the Processors Extending the Processors PowerPowerPC Cards

◦Expansion bus for laptops◦Hot swappable◦Small card size

5B-46

Extending the Processors Extending the Processors PowerPowerPlug and play

◦New hardware detected automatically

◦Prompts to install drivers

5B-47

Chapter 6Chapter 6End of Chapter

Technology

Ch6