1. Using the Keyboard And Mouse
Chapter 2A
Using the Keyboard And Mouse

2. The Keyboard The most common input device
Must be proficient with keyboard
Skill is called keyboarding
A standard keyboard uses 100 keys

3. Keyboard
The keyboard allows the computer user to enter words, numbers, punctuation, symbols, and special function commands into the computer’s memory.

4. The Keyboard The alphanumeric keys
Includes letter, numbers, Tab, Caps Lock, Backspace, Enter.

5. The Keyboard The modifier keys Shift, Alt, Ctrl The numeric keypad
10 digits and mathematical operators, Num lock

6. The Keyboard The function keys Labeled as F1, F2 etc
The cursor movement keys
Arrow signs, Page Up, Page Down
The special purpose keys
Esc, Prt Sc

7. How keyboard works How the computer accepts input from keyboard
Keyboard controller detects a key press
Controller sends a code to the Keyboard Buffer
Code represents the key pressed
Controller notifies the operating system
Operating system responds and read the code from Keyboard Buffer
The system software passes the code to the CPU.
Teaching tip
Table 5A.3 presents the ASCII code. An exercise that never fails to amuse students is to use the Alt and the number pad to enter letters into an application. As before, open MS Word. Have students hold down the Alt key and type an ASCII value into the number pad. Once they release the Alt, the letter appears. This is a useful skill when the keyboard breaks. Challenge the students to explore numbers above 128.

8. Mouse It is an input device
Moves on a flat surface and controls the pointer
Pointer is an on screen object, usually an arrow used to select text, access menus and interacts with file, data program

9. Mouse Mechanical mouse
The most commonly used mechanical mouse has a small rubber ball
When the mouse moves
The rolling mouse ball spins the roller
Information from the roller sent to the system software
Software controls the pointer

10. Mouse Non-mechanical mouse
Optical mouse is getting popularity day by day.
Light emits from underside
It uses the light’s reflection to judge direction, distance and speed

11. Mouse Benefits of mouse
Lets you position the cursor anywhere on the screen quickly without using the keyboard
Instead of typing commands through keyboard you can choose commands from menus.
Users can draw electronically

12. Mouse PS/2– Most commonly used; connects to PS/2 port or USB port.
Cordless Mouse
PS/2 Mouse
PS/2– Most commonly used; connects to PS/2 port or USB port.
Cordless– Uses infrared signals; must be within sight of the receiving port.

13. Using the Mouse Mouse buttons enable the user to initiate actions.
Clicking (left-, right-, or double-clicking) allows the user to select an item on the screen or open a program or dialog box.
Dragging– Holding down the left mouse button and moving the mouse enables the user to move objects on the screen.
Double-ckicking- pressing and releasing the mouse button twice in rapid succession
Right clicking- pressing and releasing the right button to get some shortcut menu

14. Mouse button configuration
Generally placed at the right side of user
Configured for a right-handed user
Can be reconfigured
Extra buttons are configurable
Buttons can be configured for special uses

15. Variants of the Mouse Trackballs Upside down mouse
Hand rests on the ball
User moves the ball
Uses little desk space

16. Variants of the Mouse Track pads Stationary pointing device
Small plastic rectangle
Finger moves across the pad
1.5 to 2 inch in size
Popular on laptops

17. Variants of the Mouse Track point Little joystick on the keyboard
Move pointer by moving the joystick
Placed between G and H
Saves great deal of time and effort
Insider information
The term track point is copyrighted by IBM.

18. Ergonomics and Input Devices
Study of human and tool interaction
Concerned with physical interaction
Attempts to improve safety and comfort

19. Ergonomics and Input Devices
Repetitive Stress Injury (RSI)
Caused by continuous misuse of the body
Many professions suffer from RSI who work for data entry
Carpal Tunnel Syndrome
Carpal tunnel is a passage in the wrist
Holds nerves and tendons
Prolonged keyboarding swells tendons
Teaching tip
Hairstylists often suffer from carpal tunnel. Bicyclists can suffer from overuse injuries of the knee.
Page 116 of the text has a diagram of the carpal tunnel.

20. Carpal Tunnel Syndrome

21. Ergonomics and Input Devices
Office hardware suggestions
Office chairs should have
Adjustable armrests and height
Lower back support
Desks should
Have a keyboard tray
Keep hands at keyboard height
Place the monitor at eye level

22. Ergonomics and Input Devices
Techniques to avoid RSI
Sit up straight
Have a padded wrist support
Keep your wrist straight
Learn to type
Take frequent breaks
Use ergonomic keyboard

23. Ergonomic Keyboard

24. Chapter 3A
End of Chapter