Pertemuan 3Understanding Input Peripherals

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Learning Outcomes

Pada akhir pertemuan ini, diharapkan mahasiswa akan mampu :• menjelaskan tentang contoh-contoh

perangkat input pada komputer

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Outline Materi

• Pointing Devices• Voice Input• Input Devices for Mobile User• Scanners

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What Is Input?

• What is input?

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Ø Input device is any hardware component used to enter data or instructions

Ø Data or instructions entered into memory of computer

What Is Input?

• What are the two types of input?

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§ Unprocessed text, numbers, images, audio, and video

Ø Instructions§ Programs§ Commands§ User responses

Ø Data

The Keyboard• How is the keyboard divided?

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Ø Typing areaØ Numeric keypadØ Function keys, special

keys that issue commands

The Keyboard

• What is a cordless keyboard?

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Ø Communicate with a receiver attached to a port on the system unit

Pointing Devices

• What is a mouse?

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Ø Pointing device that fits under palm of hand§ Pointing device controls

movement of pointer, also called mouse pointer

Ø Mechanical mousehas rubber or metal ball on underside

mouse buttonswheel button

mouse pad

ball

Pointing Devices

•What is an optical mouse?

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Ø No moving mechanical parts inside

Ø Senses light to detect mouse’s movement

Ø More precise than mechanical mouse

Ø Connects using a cable, or wireless

Other Pointing Devices• What is a trackball?

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Ø Stationary pointing device with a ball on its top

Ø To move pointer, rotate ball with thumb, fingers, or palm of hand

Other Pointing Devices•What are a touchpad and apointing stick?

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Ø Touchpad is small, flat, rectangular pointing device sensitive to pressure and motion

Ø Pointing stick is pointing device shaped like pencil eraser positioned between keys on keyboard

Other Pointing Devices• What are a joystick and a wheel?

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Ø Joystick is vertical lever mounted on a base

Ø Wheel is steering-wheel-type input device§ Pedal simulates

car brakes and accelerator

Other Pointing Devices• What is a light pen?

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Ø Handheld input device that can detect light§ Press light pen against

screen surface and then press button on pen

Other Pointing Devices• What is a touch screen?

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Ø Touch areas of screen with finger

Ø Often used with kiosks

Other Pointing Devices• What is a stylus?

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Ø Looks like a ballpoint pen, but uses pressure to write text and draw lines

Ø Used with graphics tablets, flat electronic boards

Other Pointing Devices• Where is a stylus used?

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Ø Some desktop computersØ Many mobile computers

and devices§ Handwriting recognition

software translates handwriting into characters that computer can process

Voice Input• How does voice recognition work?

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Step 2. An analog-to-digital converter (ADC) translates sound waves into digital measurements computer can process. Measurements include pitch, volume, silences, and phonemes. Phonemes are sound units such as aw and guh.

10010111010110101100001101

Step 3. Software compares spoken measurements with those in its database to find a match or list of possible matches.

Matches

Step 4. To narrow a list down, software presents user with a list of choices or uses a natural language component to predict most likely match. User may correct any selection made by software.

Natural Language Engine

Step 1. A user dictates text into a microphone.

Voice Input

•What is a MIDI (musical instrument digital interface)?

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Ø External device, such as electronic piano keyboard, to input music and sound effects

PDAs, Tablet PCs, and Smart Phones

•How is a data entered into a PDA?

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PDAs, Tablet PCs, and Smart Phones

•What is a portable keyboard?

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Ø Full-sized keyboard you conveniently attach to and remove from PDA

Virtual Keyboard

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PDAs, Tablet PCs, and Smart Phones

• What is a smart phone?

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Ø Users can input and send text messages, graphics, pictures, video clips, and sound files

Ø Many have a built-in or attachable camera

Digital Cameras• What is a digital camera?

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Ø Allows you to take digital pictures

Ø Images viewable immediately on camera§ Download to

computer§ Post pictures

to Web

Video Input

• What is video input?

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Ø Process of entering full-motion images into computer

Ø Video capture card is adapter card that converts analog video signal into digital signal that computer can use

Ø Digital video (DV) camera records video as digital signals

Video Input• What are a PC video camera and a Web cam?

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Ø PC video camerac—cDV camera used to capture video and still images, and to make video telephone calls on Internet§ Also called PC camera

Ø Web camc—cvideo camera whose output displays on a Web page

Video Input• What is video conferencing?

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§ Whiteboard is another window on screen that can display notes and drawings simultaneously on all participants’ screens

Ø Two or more geographically separated people who use network on Internet to transmit audio and video data

Scanners and Reading Devices

• What is a scanner?

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Flatbed

Pen or Handheld

Sheet-fed

Drum

Ø Light-sensing device that reads printed text and graphics§ Used for image processing,

converting paper documents into electronic images

Scanners and Reading Devices

• What is an optical reader?

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§ Optical character recognition (OCR) reads characters in OCR font

§ Optical mark recognition (OMR) reads hand-drawn pencil marks, such as small circles

§ Bar code scanner

Ø Device that uses light source to read characters, marks, and codes and then converts them into digital data

Scanners and Reading Devices

• What is a bar code reader?

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Ø Uses laser beams to read bar codes

Scanners and Reading Devices

• What is a data collection device?

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Ø Obtains data directly at location where transaction or event takes place

Ø Transmits data over network or Internet

Terminals

• What is a point of sale (POS) terminal?

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Ø Records purchases, processes credit or debit cards, and updates inventory§ Swipe credit or debit card

through card readerc—creads customer’s personal data from magnetic strip

Terminals

• What is an automated teller machine (ATM)?

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Ø Self-service banking machine that connects to a host computer through a network

Terminals

• What is a smart display?

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Ø Thin monitor that detaches from computer to function as portable wireless touch screen

Biometric Input

• What is biometrics?

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Ø Authenticates person’s identity by verifying personal characteristic§ Fingerprint scanner captures

curves and indentations of fingerprint

§ Hand geometry system measures shape and size of person’s hand

Biometric Input• What are examples of biometric technology?

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Ø Voice verification system compares live speech with stored voice pattern

Ø Signature verification system recognizes shape of signature

Ø Iris recognition system reads patterns in blood vessels in back of eye§ Biometric data is sometimes stored

on smart card, which stores personal data on microprocessor embedded in card

• Source : Shelly, Gary B. Discovering Computers (2004/2005/2006). Thomson Course Technology. PPT for Chapter 5.

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