Strata IT Training

Chapter 3

Common Input/Output Devices

Basic I/O Devices

• Keyboard• Mouse

– USB– Wireless

• Monitor– CRT– LCD (Flat Screen)

Keyboards• Key usage can depend on application

– Games– Function keys

• QWERTY layout (first 6 letters of top row)– Originally designed to slow typing on manual

typewriters

• Connectors– Mini-DIN or PS/2 (purple)– USB– Wireless

Keyboard Properties

• Open Control Panel• Switch to Small icon

view• Click Keyboard

– Change repeat delay and repeat rate

– Change Cursor blink rate

Mouse• Right-click

– Get information

• Left-click– Select item

• Use Control Key and Shift key to select multiple

– Double-click • Advances to that selection

• Wheel– Scroll down window

• Middle-click– Wheel is also a button– Application dependent

Mouse Connectors• Serial

– Really old– 9-pin connector

• PS/2 or Mini-DIN– Green plug

• USB – Type A• Wireless

– USB– Bluetooth

• Apple mice have one button

Changing Mouse Operations

• Open Control Panel

• Switch to Small icon view

• Click Mouse

Monitors

• CRT (Cathode Ray Tube)– Original monitor – Basically

TV Set– Power Hungry – Dangerous high voltage

• 30,000 volt capacitors

– Analog interface

• LCD (Liquid Crystal Display)– Flat Screen– Digital Interface– Lighter/Less Power– Wide aspect ratio

LCD Display Types

Passive Matrix

• Each pixel must maintain its state passively, without being driven by circuitry.

• Lower cost• Difficult to view at angle

Active Matrix

• Each pixel is attached to a transistor and capacitor which actively maintain the pixel state while other pixels are being address

• Wider viewing angle• More cost

Monitor Connectors• Video Card or

Motherboard– Video card for high speed

gaming

• VGA– 15-pin Analog -- CRTs

• DVI– Digital – LCD

• HDMI– TV and Computer video

• Devices may have multiple port types

DVI Connectors

• The DVI connector has up to 29 pins and is given one of three names, depending on which signals it implements:– DVI-D (digital only, single link

or dual link)– DVI-A (analog only)– DVI-I (integrated, combines

digital and analog in the same connector; digital may be single or dual link)

– Dual link has 6 more pins for more bandwidth

HDMI Connectors

• Carry both audio and video signals

• Connector types:– Type – A– Type – B– Type - C

Monitor Properties

• Pixels– One point– Multiple color options

require storage bits

• Resolution– Pixels across X pixels

down– Higher resolution is

clearer, but smaller

Resolutions

Aspect Ratios

• The ratio between number of pixels in height and width of screen

• The most common aspect ratios used today in the presentation of films in movie theaters are 1.85:1 and 2.39:1– 640x480 = 4:3 or 1.33– 1900x1080 = 16:9 or 1.77

Changing Monitor Properties• Right-click desktop• Left-click Personalize• Click Display• Click Adjust

Resolution• Set LCDs to max resolution

for best (clearest) results

• Orientation• If you have two

monitors attached– Select Extend

– Determine position

End of Chapter 3 Presentation