CHAPTER 3HARDWARE

CHAPTER OUTLINE

1.1 Introduction

1.2 Strategic Hardware Issues

1.3 Computer Hierarchy

1.4 Input and Output Technologies

1.5 The Central Processing Unit

LEARNING OBJECTIVES1. Identify the major hardware components of a computer system.

2. Discuss the strategic issues that link hardware design to business strategy.

3. Describe the hierarchy of computers according to power and their respective roles.

4. Differentiate the various types of input and output technologies and their uses.

LEARNING OBJECTIVES5. Describe the design and functioning of the central processing unit.

6. Discuss the relationships between microprocessor component designs and performance.

7. Describe the main types of primary and secondary storage.

8. Distinguish between primary and secondary storage along the dimensions of speed, cost, and capacity.

1.1 Introduction to Hardware

Hardware

Hardware refers to the physical equipment usedfor the input, processing, output, and storageactivities of a computer system.

Hardware consists of:Central Processing Unit (CPU)

Manipulates the data and controls the tasks performed by the other components.

Primary Storage Internal to the CPU; temporarily stores data and program instructions during processing.

Secondary Storage External to the CPU; stores data and programs for future use

Input Technologies Accept data and instructions and convert them to a form that the computer can understand.

Output Technologies

Present data and information in a form people can understand.

Communication Technologies

Provide for the flow of data from external computer networks (e.g. the Internet and intranets) to the CPU, and from the CPU to computer networks.

1.2 Strategic Hardware Issues

• The key issues with hardware are WHAT in enables and how to keep up with rapid price/ performance increases.

• In many industries, exploiting computer hardware is essential to achieving competitive advantage.

• Successful hardware exploitation come from thoughtful consideration of the following questions:-

HOW will the organization keep up with the rapid and performance advancements in

hardware

EG: How often should the

organization upgrade its

computers and storage system?

HOW should the organization

determine the need for new hardware infrastructures, such as server

farms, virtualization, grid

computing, and utility computing?

Portable computers and

advanced communications

technologies enable employees to work from home or almost any other

location.

1.3 Computer Hierarchy

• Supercomputers

• Mainframe Computers

• Midrange Computers

• Microcomputers

Supercomputers

• The faster computers available at any given time.• Supercomputers are costly as well as fast, large organizations

generally use them to execute computationally demanding tasks involving large data set.

• Typically run military and scientific applications.• Although these machines cots millions of dollars, they are also being

used for commercial applications where huge amounts of data must be analyzed.

• EG:- Large banks employ supercomputers to calculate the risks and

returns of various investment strategies, and healthcare

organizations use them to analyze giant database of patient data

to determine optimal treatments for various diseases.

Mainframe Computer

• Mainframes remain popular in large enterprise for extensive computing applications that are accessed by thousands of users simultaneously.

• EG:- Mainframes applications are airline reservation systems, corporate payroll program, website transaction processing system ( Amazon and eBay)’

• Today’s mainframes perform at teraflop speed (trillions of floating point operations per second) and can handle millions of transaction per day.

Midrange Computers

• Larges midrange computers call minicomputers, are relatively small, inexpensive, and compact computers that perform the same functions as mainframes computer.

• The lines between minicomputers and mainframes have blurred in both price and performance.

• Minicomputers are a type of server that is computer that supports computer networks and enables users to share files,

software, peripheral devices, and other resources.

MICROCOMPUTERS

• Also called micros, personal computers, or PCs are the smallest and least expensive category of general-

purpose computer.

Desktop PCs * The Desktop Personal Computer is the familiar

microcomputer system that has been a standard tool for business at the home. microcomputer

Laptop and Notebook Computers * A small, light weight microcomputers that fit easily into a briefcase. * Designed to be as convenient and easy to transport as possible. * Provide users with access to processing power and data outside an office environment. * They cost more than desktop for similar functionality.

Netbooks * Is a very small, lightweight, portable computer that is energy efficient and relatively inexpensive. * Netbooks generally optimized for Internet based services such as web browsing and e-mailing.

Tablet Computers

* Is a complete computer contained entirely in a flat touch screen that users operate via a stylus, a digital pen, or their finger tip instead of a keyboard and mouse.

* EG:- Apple iPad, HP Slate, the Toshiba Thrive and the Motorola Xoom

1.4 Input and Output Technologies

• 2 main types of input devices are HUMAN DATA ENTRY DEVICE and SOURCE DATA AUTOMATION DEVICE

HUMAN DATA ENTRY DEVICE

•implies, require a certain amount of

human effort to input data.

•EG keyboard, mouse, pointing stick, trackball, joystick, touch screen,

stylus and voice recognition.

SOURCE DATA AUTOMATION DEVICE

•With minimal human intervention.

•Speed up data collection, reduce

errors, and gather data at the source of a

transaction or other event.

•EG Barcode Readers, ATMs and radio

frequency identification

Various Human Input Devices

•Trackball

•Pointing Stick

•Digital Pen

•Wii

•Web Camera

•The Maltron Keyboard

•Bluetooth Laser •Virtual Keyboard

© MONKEY BUSINESS-LBR/Age Fotostock America, Inc.

Source: WENN Photos/NewsCom

We’ve Come a Long Way

A very early (if not the first) mouse demonstration in

1968.

See the video of Oblong’s product, called G-Speak

The First Mouse

A very early (if not the first) mouse demonstration in

1968.

Output Technologies Output generated by a computer can be transmitted to the user over several output devices and media, which include:

MonitorsPrintersPlottersVoice

Electronic Book Readers

Amazon’s Kindle 3

Sony Reader

Asus ebook Reader

Barnes and Noble Nook

© Andriy Kravchenko/Age Fotostock America, Inc.

Multimedia Technology

Multimedia technology •is the computer-based integration of text, sound, still images, animation, and digitized motion video.

Merges capabilities of computers with televisions, VCRs, CD players, DVD players, video and audio recording equipment, music and gaming technologies.

1.5 The Central Processing UnitCentral processing unit (CPU) * Performs the actual computation or "number crunching” inside any computer.

Microprocessor* Made up of millions of microscopic transistors embedded

in a circuit on a silicon chip.

Control unit sequentially accesses program instructions, decodes them and controls the flow of data to and fromthe ALU, the registers, the caches, primary storage, secondary storage and various output devices.

Arithmetic-logic unit (ALU) performs the mathematic calculations and makes logical comparisons

Registers are high-speed storage areas that store very small amounts of data and instructions for short periods of time.

Central Processing Unit (CPU)

How the CPU Works

•The inputs consist of data and brief instructions about what to do with the data These instructions come from software in other parts of the computer. Data might be entered by the user through the keyboard, for example, or read from a data file in another part of the computer. The inputs are stored in registers until they are sent to the next step in the processing.

•Data and instructions travel in the chip via electrical pathways called buses. The size of the bus analogous to the width of a highway determines how much information can flow at any time.

•The control unit directs the flow of data and instructions within the chip.

•The arithmetic-logic unit (ALU) receives the data and instructions from the registers and makes the desired computation. These data and instructions have been translated into binary form, that is, only 0s and 1s. The CPU can process only binary data.

•The data in their original form and the instructions are sent to storage registers and then are

• sent back to a storage place outside the chip, such as the computer’s hard drive .

•Meanwhile, the transformed data go to another register and then on to other parts of the computer (to the monitor for display or to storage, for example)

Advances in Microprocessor Design

Moore’s Law: microprocessor complexity would double every two years.

The Evolution of Chips

For a look at the evolution of chips from the Intel 4004 to multicore chips, click here.

Computer Memory2 basic categories of computer memory:

Primary Storage * Stores small amounts of data and information that will be immediately used by the CPU.

Secondary Storage * stores much larger amounts of data and information (an entire software program, for example) for extended periods of time.

Memory Capacity:Bit: Short for binary digit (0s and 1s), the only data that a CPU can process.

Byte: An 8-bit string of data, needed to represent any one alphanumeric character or simple mathematical operation.

Hierarchy of Memory Capacity

Kilobyte(KB) approximately one thousand bytes

Megabyte(MB)

approximately one million bytes (1,048,576 bytes, or 1,024 x 1,024).

Gigabyte(GB) actually 1,073,741,824 bytes (1,024 x 1,024 x 1,024 bytes).

Terabyte One trillion bytes.

Petabyte One thousand terabytes.

Exabyte One thousand petabytes.

Zettabyte One thousand exabytes.

Main Types of Primary StorageRegisters: registers are part of the CPU with the least

capacity, storing extremely limitedamounts of instructions and data only immediately before and after processing

Random access memory (RAM):

The part of primary storage that holds a software program and small amounts of data when they are brought from secondarystorage.

Cache memory: A type of primary storage where the computer can temporarily store blocks of data used more often.

Read-only memory (ROM):

Type of primary storage where certain critical instructions are safeguarded, the storage isnonvolatile and retains the instructions when the power to the computer is turned off.

Primary Storage

Register

RAM

Cache

MRAM

© Aleksandr Potapov/Age Fotostock America, Inc.

* Register – They have the least capacity, storing extremely limited amounts of instruction and data only immediately before and after

processing

* Cache Memory – is a type of high- speed memory that a processor can access more rapidly the main memory (RAM).

-Enables the computer to temporarily store frequently used block used infrequently remain secondary storage.

-- Cache is faster than RAM

*Random Access Memory (RAM) – Is the part of primary storage that holds a software program and small amount of data for

processing.- When a software program (such as Microsoft Word) is started, the

entire program is transferred from secondary storage into RAM.-RAM stores more information and is located farther away from the

CPU.- RAM is temporary and Volatile Memory = Loses its content

when power is turned off

•Read- Only Memory(ROM) – is the place- Nonvolatile Memory = Does not lose contents when power is

removed (ROM, FLASH MEMORY)-Read Only designation means that instruction in ROM can only be

read, not changed.- EXAMPLE: ROM is the initial instructions needed to start or “boot”

the computer.

Internal workings of personal computer

RAM

Hard disk drive

Floppy disk drive

CPU board with fan

Primary versus Secondary Memory

Secondary Storage

Memory capacity that can store very large amounts of data

for extended periods of time.

Magnetic tape (sequential access)Magnetic disks (direct access)Optical storage devicesFlash memory devices

•It is nonvolatile.•It takes much more time to retrieve data because of the electromechanical nature. •It is cheaper than primary storage.•It can take place on a variety of media

Magnetic tape : A secondary storage medium on a large open reel or in a smaller cartridge or cassette.

Magnetic disks : A form of secondary storage on a magnetized disk divided into tracks and sectors

that provide addresses for various pieces of data; also called hard disks.

Magnetic disks : A form of secondary storage on a magnetized disk divided into tracks and sectors

that provide addresses for various pieces of data; also called hard disks.

Optical Storage : Laser reads the surface of a reflective plastic platter.

Are slower than magnetic hard drives but they are less susceptible to damage from contamination, and less fragile.

Flash Memory : Are used with digital camera, handheld and laptop computers, telephones, music players and video

game consoles.

Flash Memory : Are used with digital camera, handheld and laptop computers, telephones, music players and video

game consoles.

Hard Drive

Source: BraginAlexey/Shutterstock

Hard drives: A form of secondary storage that stores data on platters divided into concentric tracks and sectors, which can be ready by a read//write head that pivots across the rotating disks.

Optical Storage Devices

Optical storage devicesA form of secondary storage in which a laser reads the

surfaceof a reflective plastic platter.

© J R Bale, Balefire C/Age Fotostock America, Inc.

Compact disk, read-only memory (CD-ROM): A form of secondary storage that can be only read and not written on.

Digital video disk (DVD): An optical storage device used to store digital video or computer data.

Flash Memory DevicesFlash memory : non-volitile memory that can be erased

and reprogrammed.

Flash memory devices : electronic storage devices with no

moving partsThumb drive