Mongolia International University

Chapter 5Chapter 5

B.M.HB.M.H

Input and OutputInput and Output

Computers MIU

Learning ObjectivesLearning Objectives

KeyboardKeyboard Pointing DevicesPointing Devices

Mouse, Trackball, Touchpad, Pointing stickMouse, Trackball, Touchpad, Pointing stick Joystick, Graphics tablet, Touch screensJoystick, Graphics tablet, Touch screens Pen-based computingPen-based computing

Source Data AutomationSource Data Automation Magnetic-ink character recognitionMagnetic-ink character recognition Optical recognition devicesOptical recognition devices Voice outputVoice output

Computers MIU

Computer systemComputer system

Input Processing Output

SecondaryStorage

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InputInput

Input data Input data Go directly to the computer for processingGo directly to the computer for processing

Bar codes, Speech through a microphone Data by means of a device that converts motions to on-

screen action Go through intermediate handlingGo through intermediate handling

Copied from a source document and translated to a Magnetic disk

Called rawdata.

Computers MIU

Conventional input Conventional input devicesdevices

KeyboardKeyboard Pointing devicesPointing devices

Computers MIU

KeyboardKeyboard

Part of a PC or a terminalPart of a PC or a terminal A traditional keyboardA traditional keyboard

A keyboard of supermarket A keyboard of supermarket or fast-food franchiseor fast-food franchise

Its keys represent items such as large fries or a Big Mac.

A keyboard to enter other A keyboard to enter other language characterslanguage characters such as a such as a Chinese characters.Chinese characters.

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Pointing devicesPointing devices

Used to position a Used to position a pointerpointer on the screen on the screen PointerPointer

Has a number of shapes but most is often an arrow Has one or more buttonsHas one or more buttons

To set the To set the insertion pointinsertion point or or cursor cursor To communicate commands to the OS or To communicate commands to the OS or

an application program by clicking a button an application program by clicking a button Often used to click on an icon in GUI

IconIcon A pictorial symbol on a screen Represents a computer activity (a command to the computer)

GUI (graphical user interface)GUI (graphical user interface) The environment that permits communication with the computer

clicking on icons

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Pointing devicesPointing devices

Types Types MouseMouse TrackballTrackball TouchpadTouchpad Pointing stickPointing stick JoystickJoystick Graphics tabletGraphics tablet Touch screensTouch screens Pen-based computingPen-based computing

Computers MIU

MouseMouse

The most common pointing device for PCsThe most common pointing device for PCs Types Types

Mechanical mouseMechanical mouse Uses a small ball on its underside

Sensors inside the mouse determine the direction and distance of movement

Optical mouseOptical mouse Uses a light beam to monitor mouse movement

Wireless mouseWireless mouse Communicate through an infrared beam without cable

Wheel mouseWheel mouse Has an extra wheel that can be clicked like a button or rolled

to affect the cursor

Computers MIU

Computers MIU

Computers MIU

TrackballTrackball

A variation on the mechanical mouseA variation on the mechanical mouse Roll the ball directly with your handRoll the ball directly with your hand Used to play a video gameUsed to play a video game

Computers MIU

Computers MIU

TouchpadTouchpad

A rectangular A rectangular pressure-sensitivepressure-sensitive padpad Slide a finger across the surfaceSlide a finger across the surface

Buttons at the bottom of the unitButtons at the bottom of the unit The same functions as mouse buttonsThe same functions as mouse buttons

Recognize Recognize a finger tap as a clicka finger tap as a click

Computers MIU

Computers MIU

Computers MIU

Pointing stickPointing stick

A small pressure-A small pressure-sensitive postsensitive post mounted in the center mounted in the center

of the keyboard of the keyboard between the G and H between the G and H keyskeys

Pushing the post in Pushing the post in one direction one direction Causes it to move in Causes it to move in

that directionthat direction

Computers MIU

Computers MIU

Joystick Joystick

A short lever with a handgripA short lever with a handgrip The distance and speed of The distance and speed of

movementmovement Control the screen pointerControl the screen pointer’’s positions position

Most often used with gamesMost often used with games such as flight simulatorssuch as flight simulators

Computers MIU

Computers MIU

Graphics tabletGraphics tablet

Called a Called a digitizing tabletdigitizing tablet A rectangular board with an invisible A rectangular board with an invisible

grid of electronic dotsgrid of electronic dots used a pen-like stylus or a mouse-like used a pen-like stylus or a mouse-like

puckpuck

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Computers MIU

Touch screensTouch screens

One way of getting input directly from One way of getting input directly from the source the source

Point to a selectionPoint to a selection

Computers MIU

Computers MIU

Pen-based computingPen-based computing

Use an electronic Use an electronic pen, or styluspen, or stylus to input to input datadata Used as a pointer on the screenUsed as a pointer on the screen Used to input data in handwritten formUsed to input data in handwritten form

Computers MIU

Computers MIU

Source Data AutomationSource Data Automation

The use of special equipment to collect data at The use of special equipment to collect data at the source (efficient data input)the source (efficient data input) Send it directly to the computerSend it directly to the computer

- supermarket bar code eliminates keying- supermarket bar code eliminates keying Reduce the number of intermediate stepsReduce the number of intermediate steps

→ → Reduce costs and opportunities for human mistakes.Reduce costs and opportunities for human mistakes. The primary areasThe primary areas

Magnetic-ink character recognitionMagnetic-ink character recognition Optical ScannersOptical Scanners Other optical recognition devicesOther optical recognition devices Voice, finger or eyeVoice, finger or eye

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MICRMICR

: : MMagnetic-agnetic-IInk nk CCharacter haracter RRecognitionecognition Involves using a machine to read Involves using a machine to read

character made of magnetized particlescharacter made of magnetized particles Ex. Banking industryEx. Banking industry

the numbers encoded across the bottom of the numbers encoded across the bottom of personal checkpersonal check

These numbers should correspond to the These numbers should correspond to the amount of the check.amount of the check.

Computers MIU

Computers MIU

Optical Scanner Optical Scanner

ConvertConvert text or even a drawing or text or even a drawing or picture picture into computer-recognizable data into computer-recognizable data by using a form of optical recognitionby using a form of optical recognition

Optical recognition systemOptical recognition system Use a light beamUse a light beam to scan input data and to scan input data and

convert it into electrical signalsconvert it into electrical signals CategoriesCategories

Flatbed scannerFlatbed scanner Sheet-feed scannerSheet-feed scanner Handheld scannerHandheld scanner

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Flatbed scanner

Sheetfed scanner

handheld scanner

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More optical recognition More optical recognition methodsmethods

OOptical ptical MMark ark RRecognition (OMR)ecognition (OMR) OOptical ptical CCharacter haracter RRecognition (OCR)ecognition (OCR) Bar codesBar codes Handwritten charactersHandwritten characters

Computers MIU

OMROMR

Called Called Mark sensingMark sensing A machine senses A machine senses

marks on a piece of marks on a piece of paperpaper

Ex. TestEx. Test’’s answer s answer sheetsheet

Exam

1. O O O O

2. O O O O

3. O O O O

4. O O O O

5. O O O O

a b c d

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OCROCR

Use Use a light sourcea light source to to read special characters read special characters and convert them into and convert them into electrical signalselectrical signals

OCR-AOCR-A A standard typeface for A standard typeface for

optical characteroptical character Established by the ANSIEstablished by the ANSI Can be read by both Can be read by both

humans and machineshumans and machines

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Bar codeBar code

The code number represented on the The code number represented on the product label by a pattern of product label by a pattern of vertical vertical marks, or barsmarks, or bars

Barcode readerBarcode reader sense and read these stripessense and read these stripes A photoelectric device that reads the code A photoelectric device that reads the code by by

mean of reflected lightmean of reflected light

Computers MIU

Computers MIU

Computers MIU

Handwritten charactersHandwritten characters

Machines that can read handwritten Machines that can read handwritten characterscharacters make handwritten data immediately usable make handwritten data immediately usable

for processing for processing Legibility of the handwriting are rigidLegibility of the handwriting are rigid

Computers MIU

Computers MIU

Voice inputVoice input

Speaking to a computerSpeaking to a computer Called Called speech recognitionspeech recognition Speech recognition devicesSpeech recognition devices

Accept the spoken word through a microphone Accept the spoken word through a microphone and convert it into binary code(0s and 1s)and convert it into binary code(0s and 1s)

The disabled,those with The disabled,those with ““busy handsbusy hands””,hands too ,hands too dirty for the keyboard are using.dirty for the keyboard are using.

Computers MIU

Computers MIU

Digital CamerasDigital Cameras

Takes photos that it stores internally on Takes photos that it stores internally on a chipa chip No filmNo film Photos sent by cable directly to a computerPhotos sent by cable directly to a computer