Introduction to computer hardware

Introduction to ITIntroduction to IT

MBAMBA

IMS University of PeshawarIMS University of Peshawar

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Course ObjectivesCourse Objectives Computer is one of the most advanced and fast growing

technologies of the world. Each and every day a lot of improvement is emerging in both Software and Hardware of the computer.

In response to this trend this course has been designed.

It focuses on brief Introduction to Computers History and Types of computer, the Basics Concepts of Computer Software, Hardware and Input/Output Device.

Basic aspect of Information Technology, Social Impacts of Information Technology and Policies.

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Week-1Week-1

IntroductionIntroduction Introduction to Computer ApplicationIntroduction to Computer Application ComputerComputer Information TechnologyInformation Technology Organization of ComputerOrganization of Computer

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ComputerComputer The word computer comes from the Latin word “computa” which

means “to calculate”. A computer is normally considered as calculating machine that

can perform arithmetic operation at a very high speed.

It is not only a machine which perform different functions on numeric data but today more than 80% work perform by computer is non numeric in nature.

Nowadays computer is used for multiple purposes.

An electronic device which is capable of performing series of An electronic device which is capable of performing series of arithmetic and logical operations at a very high speed is arithmetic and logical operations at a very high speed is

called computer.called computer.

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Computer (Computer (Cont’dCont’d)) So what will be the more elaborate definition of computer??

All computer processing requires data, which is a collection of raw facts, figures and symbols, such as numbers, words, images, video and sound, given to the computer during the input phase.

Computers manipulate data to create information with the help of CPU.

Information is data that is organized, meaningful, and useful.

Computer is an electronic device which takes certain input Computer is an electronic device which takes certain input (Data)(Data), manipulate that input , manipulate that input (Process)(Process), store it in memory or , store it in memory or storage devices and then gives the desired results storage devices and then gives the desired results (Output).(Output).

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Computer (Computer (Cont’dCont’d)) Memory is an area of computer which holds data that is

Waiting to be processed, Storing or output The information can also be put in computer storage for future

use. During the output Phase, the information that has been created

is put into some form, at output devices.

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Computer OrganizationComputer Organization

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Information Technology

First you have to understand the differences between science, engineering & technology.

Science is a systematic & specialized way of thinking. A Science is a systematic & specialized way of thinking. A scientist thinks & makes principles & hypothesisscientist thinks & makes principles & hypothesis.

Engineering means the practical implementation of principles & Engineering means the practical implementation of principles & hypothesis for the welfare of human beings with the help of hypothesis for the welfare of human beings with the help of

machines. At first he makes drawings on the basis of principles, machines. At first he makes drawings on the basis of principles, and then take it to real world for use.and then take it to real world for use.

Technology always deals with OPTIMIZATION (MAXIMUM GAIN Technology always deals with OPTIMIZATION (MAXIMUM GAIN WITH MINIMUM EFFORTS) with the help of newer supports like WITH MINIMUM EFFORTS) with the help of newer supports like

computers & transfer machines. computers & transfer machines. The aim of IT is to make our information more profitable by The aim of IT is to make our information more profitable by

making it recently & attractive.making it recently & attractive.

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Information Technology is the application of Computers towards organizing and efficient retrieval/reporting of information.

Information Technology refers to the creation, gathering, Information Technology refers to the creation, gathering, processing, storing, protecting, presenting and dissemination of processing, storing, protecting, presenting and dissemination of information using information using , , hardware, software and telecommunication hardware, software and telecommunication

technology.technology.

Information Technology (Cont’d)

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Introduction to Computer HardwareIntroduction to Computer Hardware Introduction to Computer HardwareIntroduction to Computer Hardware

System UnitSystem Unit MotherboardMotherboard

BIOSBIOS Basic Unit of MeasurementBasic Unit of Measurement ProcessorProcessor MemoryMemory

RAMRAM ROMROM

Storage DevicesStorage Devices Magnetic Storage DevicesMagnetic Storage Devices

FormattingFormatting Optical Storage DevicesOptical Storage Devices

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HardwareHardware

The physical components of a computer is called Hardware. The physical (electronic and mechanical) parts of a computer is

called Hardware. Hardware is one that is tangible. The storage devices (Hard disk, CD’s etc.,), mouse, keyboard

CPU and display devices (Monitor) are Hardware. The hardware devices attached to the computer are called

peripheral devices.

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System UnitSystem Unit The System Unit is a case which is just like a box made up of a

metal or plastic. This casing actually contain the electronic components of a computer used to process data.

The casing is some time called Chassis, that protect the internal electronic components from damage.

The most important component of this System box is Mother Board. All the components are then installed on this Mother Board.

System Unit consist of the following devices:- Mother Board Processor Memory Disk systems

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System Unit (Cont’d)System Unit (Cont’d)power supply

ports

drive bays

processor

memory

sound card

video cardmodem cardnetwork card

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Mother BoardMother Board It is the main circuit board of the system unit.

It is the centralized platform where all the hardware components of a computer are connected.

Many electronic components are attached to the mother board, others are built-in on it.

Each and every Motherboard has a small battery cell.

It gives to Motherboard a small amount of power to remember the settings such as hardware configurations, date and time etc

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System Unit (Cont’d)System Unit (Cont’d)

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System Unit (Cont’d)System Unit (Cont’d)

processor chipadapter cards

memory chips

memory slots

motherboard

Expansionslots for adapter cards

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Mother Board (Cont’d)Mother Board (Cont’d) BIOS is kind of software which holds the most important data for

machine. It informs the PC about the compatibility of Motherboard with

different hardware components such as CPU etc… It is the most important component which resides in the ROM

(Read Only Memory) of the Motherboard.

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Basic Units Of MeasurementBasic Units Of Measurement BIT

BInary digiT Smallest unit of measurement Two possible values 0 & 1

ON OFF or

BYTE

8 bits

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Basic Units Of Measurement Basic Units Of Measurement ((Processor And Memory Speed))

Millisecond (ms) – a thousandth of a second (1/1,000 = 10-3) Microsecond (µs) - a millionth of a second (1/1,000,000 = 10-6) Nanosecond (ns) – a billionth of a second (1/1,000,000,000 = 10-9)

Large Units Of Measurement (Memory, Storage) Note: powers of two are used because computer memory and

storage are based on the basic unit (bit). Kilobyte (KB) – a thousand bytes (1,024 = 210) Megabyte (MB) -1,024 KB - a million (1,048,576 = 220) Gigabyte (GB) –1,024 MB - a billion (1,073,741,824 = 230) Terabyte (TB) – a trillion (1,099,511,627,776 = 240)

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ProcessorProcessor The Processor is also called Central Processing Unit (CPU). All the CPUs looks very similar, but they are different in the way,

they have different numbers of pins and different layouts.

The processor significantly impact over all computing power & manages most of computer operations.

Some computer manufacturer use the term Microprocessor which refers to a personal computer chip.

Most PC’s today use processors manufactured by IntEL, AMD etc..

“Central Processing Unit (CPU) is an electronic device that interprets and carries out the instructions that operates the computer.

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Processor (Cont’d)Processor (Cont’d)

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Processor (Processor (Cont’dCont’d)) The combination of Arithmetic Logic Unit and Control Unit is

called as Central Processing Unit (CPU). OR The two main parts of CPU are ALU & CU.

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Processor (Processor (Cont’dCont’d)) Registers are the part of the processor, not a part of memory

or storage devices. It contain different type of registers, each with a specific

storage functions. E.g. General purpose registers used for arithmetic operations & data movement. AX, BX, CX, DX

Register function includes Storing the location from where an instruction is fetched, Storing the location while the CU encode/decode it, Storing data while the ALU compute it and Storing the results after a calculation.

Today, most PCs have 32-bit registers, mean the CPU can process four bytes of data at one time.

Register sizes are rapidly growing to 64 bits.

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Multi-Core ProcessorMulti-Core Processor A Multi-Core Processor is a processing system composed of two or

more independent cores. The cores are typically integrated onto a single integrated circuit die(known as a chip multiprocessor or CMP).

Core Basic processing area of a computer processor Die A die in the context of integrated circuits is a small block of

semiconducting material, on which a given functional circuit is fabricated.

A medium-scale integrated circuit die

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Multi-Core Processor Multi-Core Processor (Cont’d)(Cont’d)

A Dual-Core and Core 2 Duo Processor contains two cores, and a Quad-Core Processor contains four cores.

A Multi-core processor implements multiprocessing in a single physical package.

Cores in a multi-core device coupled together tightly. Cores may or may not share caches. Dual Core and Core 2 Duo’s are both dual core processor. Core2 duo only takes advantage because The Core 2 Duo has the same L2 cache but it has more cache size than

a Dual core. However, There are architectural changes to the silicon that give the Core 2 Duo

more sophisticated processing. The single- and dual-core models are single-die, whereas the quad-core

models comprise two dies, each containing two cores, packaged in a multi-chip module.

Differences between Dual Core, Core 2 Duo, Core i3, Core i5, Core i7. Cache memory and Core’s

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Memory The electronic component which provides storage capability to a

computer is called Memory. Memory contains one or more sets of

chips that store data/program instructions need processing, either temporarily or permanently.

All the computers which are used today needs memory or storage capability.

The CPU accesses each location in memory by using a unique number, called the memory address.

Each byte stored in unique location called an address, similar to addresses on a passenger train

Seat #2B4 Seat #2B3

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Memory Memory (Cont’d)(Cont’d)

The are two types of Memory Random Access Memory Read Only Memory

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Random Access MemoryRandom Access Memory RAM is also called volatile memory and Keeps the information for

a shorter period of time because RAM Lost information if powered off or the computer is shutdown.

RAM store data or instructions, the computer then uses these instructions to perform any processing work.

The contents of RAM change rapidly and often. Typical ranges from Mega Bytes to Giga Bytes Random Access means direct access to any part of memory

The more RAM a The more RAM a computer has, the computer has, the faster it respondsfaster it responds

Also called Also called main memorymain memory

or or primary primary storagestorage

Most RAM is Most RAM is volatilevolatile, it is lost , it is lost when computer’s when computer’s

power is power is turned offturned off

Memory chips that can be Memory chips that can be read from and written read from and written

to by processorto by processor

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How do program instructions transfer in and out of RAM?How do program instructions transfer in and out of RAM?

Step 1. When you start the computer, certain operating system files load into RAM from the hard disk. The operating system displays the user interface on the screen.

Operating system Operating system instructionsinstructions

Operating system Operating system interfaceinterface

RAM

RAM

Web browser program Web browser program instructions are instructions are

removed from RAMremoved from RAM

Web browser Web browser window no longer is window no longer is displayed on desktopdisplayed on desktop

Step 2. When you start a word processing program, the program’s instructions load into RAM from the hard disk. The word processing program, along with the Web Browser and certain operating system instructions are in RAM. The word processing program window is displayed on the screen.

Step 3. When you quit a program, such as the Web browser, its program instructions are removed from RAM. The Web browser no longer is displayed on the screen.

Word processing Word processing program instructionsprogram instructions

Word processing Word processing program windowprogram window

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Where does Memory Reside?Where does Memory Reside?

Resides on small Resides on small circuit board called circuit board called memory modulememory module

Memory slotsMemory slots on on motherboard hold motherboard hold memory modulesmemory modules

memory chip memory slot

dual inline memory module

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Random Access Memory Random Access Memory (Cont’d)(Cont’d)

The amount of RAM in a PC has a direct affect on the system's speed.

The more RAM a PC has, the more program instructions and data can be held in memory, which is faster than storage on disk.

More RAM = Better Performance !

There are two types of RAM Dynamic RAM Static RAM

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Random Access Memory Random Access Memory (Cont’d)(Cont’d)

Dynamic RAM Dynamic RAM (DRAM) chips must be recharged with

electricity very frequently, or they will lose their contents. DRAM is further divided in two types

SDRAM DDR-SDRAM

It achieves twice the bandwidth of the preceding single data rate SDRAM

Static RAM Static RAM (SRAM) does not need to be recharged as often as

DRAM, and can hold its contents longer.

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Random Access Memory Random Access Memory (Cont’d)(Cont’d)

DDR SDRAM DDR 2 SDRAM

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Read Only MemoryRead Only Memory ROM is non-volatile memory. The kind of memory is generally programmed by manufacturer. It contains information that is permanently stored. The contents of ROM are set during manufacturing process. Most

of the ROMs are special purpose memories. Example of ROM is BIOS (Basic Input Output System).

TYPES OF ROM

PROM (Programmable Read Only Memory) Normally ROM’s are not writable but PROM’s are writable. Data can

be written to PROM’s using special devices. Data once written cannot be removed. Ultraviolet Rays are used to

write data in PROM’s.

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Read Only Memory (Cont’d)Read Only Memory (Cont’d)

EEPROM (Electronically Erasable Programmable Read Only Memory)

EEPROM needs an electric impulse to write or erase data. It has all the features of EPROM except the difference of

erasing technique i.e. it uses electric impulse instead of ultraviolet light rays for erasing.

Therefore erasing can be achieved through the use of keyboard commands without removing the chip physically from the computer.

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Cache MemoryCache Memory Cache memory is high-speed memory that holds the most recent

data and instructions that have been loaded by the CPU. Cache is located directly on the CPU or between the CPU and RAM,

making it faster than normal RAM. CPU-resident cache is called Level-1 (L1) cache. L1 cache usually has a very small capacity, ranging from 8 KB

to 128 KB. The most common size is 128 KB. Level-2 (L2) cache.

L2 cache is slower then L1 cache but has much larger capacity, ranging from 64 KB to 4 MB.

The amount of cache memory has a tremendous impact on the computer's speed.

When the processor needs an instruction or data, it searches memory in this order, L1 cache, then L2 cache, then RAM.

If the instructions or data is not found in memory then it must search a slower speed storage medium such as a hard disk, compact disc etc.

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Storage DevicesStorage Devices Storage devices holds data, instructions & information for future

use. Every computer uses storage devices to holds software,

specifically system software & application software's. It is also called Secondary Storage or Auxiliary Storage Devices. Example of storage media are Magnetic Storage Devices

Hard Disk Drive, Floppy Disk

Optical Discs: CD-R, CD-RW, DVD

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Hard DisksHard Disks

Auxiliary storage is a hard disk. Hard disks use multiple platters, stacked on a spindle. or A hard disk consists of one or more rigid metal plates coated with a

metal oxide material that allows data to be magnetically recorded on the surface of the platters.

Each platter has two read/write heads, one for each side. The hard disk platters spin at a high rate of speed, typically 5400 to

7200 RPM. Storage capacities of hard disks for personal computers range from 10

GB to 320 GB (TB is possible but rare). Read/write heads

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FormattingFormatting Formatting is the process of preparing a disk for reading and writing. Before a magnetic disk can be used, it must be formatted—a process

that maps the disk's surface and determines how data will be stored. During formatting, the drive creates circular tracks around the disk's

surface, then divides each track into sectors. The OS organizes sectors into groups, called clusters, then tracks

each file's location according to the clusters it occupies.

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Hard DiskHard DiskSectorseach track is divided into pie-shaped wedges

Clustertwo or more sectors combined

Tracksdata is recorded in circular bands

The hard disks available today is called an optically assisted hard drives. It combines optical technology with magnetic media, which have potential storage capacity up to 500 GB.

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Optical Storage DevicesOptical Storage Devices An optical disc is a high-capacity storage medium. An optical drive uses

reflected light to read data. To store data, the disc's metal surface is covered with tiny dents (pits)

and flat spots (lands), which cause light to be reflected differently. When an optical drive shines light into a pit, the light cannot be

reflected back. This represents a bit value of 0 (off). A land reflects light back to its source, representing a bit value of 1 (on).

01

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Optical Storage Devices (Cont’d)Optical Storage Devices (Cont’d) CD's (Compact Disc) 700 MB storage

CD-ROM (read only) CD-R: (Record) to a CD CD-RW: Can write and erase CD to reuse it (Re-Writable) DVD (Digital Video Disc)

A compact disk (CD), also called an optical disc, is a flat round, portable storage medium that is usually 4.75 inch in diameter.

A CD-ROM (read only memory), is a compact disc that used the same laser technology as audio CDs for recording music.

In addition it can contain other types of data such as text, graphics, and video.

The capacity of a CD-ROM is 650 MB of data, about 70 minutes of audio.

Once data is written to a standard CD-ROM disk, the data cannot be altered or overwritten.

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Optical Storage Devices (Cont’d)Optical Storage Devices (Cont’d) A CD-Recordable (CD-R) drive lets you record your own CDs, but

data cannot be overwritten once it is recorded to the disk. A CD-Rewritable (CD-RW) drive lets you record a CD, then write

new data over the already recorded data. A variation of CD-ROM is called Digital Video Disk Read-Only

Memory (DVD-ROM), and is being used in place of CD-ROM in many newer PCs.

Standard DVD disks store up to 4.7 GB of data—enough to store an entire movie.

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Optical Storage Devices (Cont’d)Optical Storage Devices (Cont’d) Dual-layer DVD disks can store up to 9.4 GB. DVD disks can store so much data because of sophisticated data

compression technologies. At a glance, a DVD-ROM look like a CD-ROM, the size and shape

are similar, but DVD-ROM store data, instructions & information in a slightly

different manner and thus it achieves high storage capacity.

HD-DVDs can store 15 GB

Blue-Ray DVDs can store 25 GB