Computing Fundamentals Lecture - 3

Dr. Hafiz Adnan Habib

Computer Engineering Department

UET Taxila

Keyboard and Mouse

• In a Computer

CPU ---> brain

Keyboard and mouse ---> Sensory organs

Keyboard and Mouse

• From user perspective

Interaction with CPU ---> Indirectly

Keyboard and mouse ---> Directly

Keyboard

Keyboard

Keyboard Layout

• QWERTY (pronounced KWER-tee)

• On this keyboard

– Alphanumeric Keys

– Modifier Keys

– Numeric Keypad

– Function Keys

– Cursor Movement Keys

– Special Purpose Keys

Keyboard Operation

Think about sequence of operations in keyboard when user presses the key?

Keyboard Operation

Keyboard Controller

Keyboard Buffer

System Software

CPU

Key Pressed on Keyboard

Sends scan code

Interrupt System

Software

Read Scan code and

pass

Mouse

Magic Mouse by Apple

http://en.wikipedia.org/wiki/Apple_Mouse

Ergonomics and Input Devices

• Ergonomics is a study of designing equipment and devices that fit human body and its cognitive abilities

• Human factors and ergonomics are employed to fulfill the goal of health, safety and productivity

http://en.wikipedia.org/wiki/Human_factors_and_ergonomics

Devices for the Hand

• Pens

• Touch Screens

Optical Input Devices

• Bar Code Readers

• Image Scanners and Optical Character Recognition (OCR)

Barcode Reader

• Barcode reader is electronic device to read printed bar codes

• A barcode is an optical machine readable representation of data

Quick Response Code

• Faster readability

• Greater storage capacity

Image Scanner and Optical Character Recognition

• OCR is conversion of scanned image into machine-encoded text

• Scanned image may have – Typewritten or printed text

– handwritten

http://en.wikipedia.org/wiki/Optical_character_recognition

Apps for OCR

• Capture image

• Analyze image

• Convert to text

https://play.google.com/store/apps/details?id=com.smartmobilesoftware.mobileocrfree

OCR Applications

What are the possible applications of OCR?

Audiovisual Input Devices

• Microphones

• Video Input

Microphone

• Microphone is acoustic to electric transducer (sensor) that converts sound into electrical signal

http://en.wikipedia.org/wiki/Microphone

MIDI: Musical Instrument Digital Interface

MIDI is a technical standard for communication between electronic musical instruments and computer

Music Processing

• Center for Digital Music, Queen Mary University London

Digital Cameras

• A digital camera encodes digital images and videos digitally and store them for later production

Digital Camera Examples

• Web cams for video conferencing

• IP Cameras for video surveillance

• High Definition Cameras

High Definition Camera Standards

Your Thinking

Can you think any advancement in the design of devices/apps used in

interaction with computers