Input Devices and Methods

1. Input Devices and Methods • Objectives: • To understand what input devices are. • Identify their individual uses • Be able to identify the difference between manual and automated input devices.

2. Input Devices and Methods Manual input devices are used by people to enter data by hand. • Keyboard • Pointing devices • Joystick • Digital camera • Touch screen • Scanner • Concept keyboard • Graphics tablet • Microphone

3. Keyboard • The keyboard is the most common type of input device. • Ordinary computer keyboards have their keys arranged in a similar way to those on a typewriter. • This way of arranging the keys is called QWERTY because of the order that the keys appear in on the first row of letters.

4. Pointing devices A mouse is a pointing device. It is the next most common type of input device after the keyboard. Touch pads and trackballs are also types of pointing device. They are often used instead of a mouse on portable computers.

5. Joystick • The main use of a joystick is to play computer games by controlling the way that something moves on the screen. • Joysticks can be used to control movement from side-to-side, up-and-down and diagonally. • A joystick will also always have at least one button on it which can be used to make something happen like making a character in a game jump or fire a gun.

6. Touch screen • A touch screen can detect exactly where on its surface it has been touched. • Touch screens are used in a lot of fast food chains and restaurants because they are easy to keep clean and re-program if changes need to be made to the menu.

7. Digital camera • A digital camera can store many more pictures than an ordinary camera. • Pictures taken using a digital camera are stored inside its memory and can be transferred to a computer by connecting the camera to it. • A digital camera takes pictures by converting the light passing through the lens at the front into a digital image.

8. Scanner • A scanner can be used to input pictures and text into a computer. • There are two main types of scanner • Hand-held • Flat-bed.

9. Concept keyboard • Flat board with a grid of programmable keys on its surface. • A single key or a group of keys can be set up to carry out a particular task. • Paper overlays are placed on top of the keyboard with pictures drawn on them to represent what will happen if the keys in a certain position are pressed. • Often used with young children in primary schools who can’t use an ordinary keyboard very well.

10. Graphics tablet • Has a flat surface and a pen, or stylus, which can be used to produce freehand drawings or trace around shapes. • When the special pen touches the surface of the graphics tablet data about its position is sent to the computer. • This data is used to produce on the screen an exact copy of what is being drawn on the surface of the graphics tablet.

11. Microphone A microphone is used to input sound into a computer system. • Often used for voice recognition systems which convert sounds made by a user into commands that the computer can carry out. • Useful for people who can’t use ordinary input devices such as the mouse and keyboard. • As computers become more powerful in the future, voice recognition will be a much more common input method for all computer users.

12. Input Devices and Methods Automated input devicescan input data automatically without any need for human intervention…

13. Bar Code Reader • Used to read the code on a bar code • It uses a laser beam that is sensitive to the different reflections from the lines and the spaces. • The reader translates the reflected light into digital data that is transferred to a computer for immediate action or storage. • Commonly used in supermarkets and libraries

14. Optical Mark Recognition (OMR) • Similar to a bar code reader but uses infra-red light to scan marks on prepared forms • multiple-choice examination answer sheets • lottery tickets.

15. Magnetic Ink Character Recognition (MICR) • Uses special ink which contains iron particles that can be magnetised and then read when the printed numbers passes through a MICR reading machine. • It is expensive, • MICR is mainly used by banks. • The account number, the cheque number and the branch number are pre-printed on a cheque.

16. Sensors • Detect changes in the physical or chemical environment and convert them into electrical signals. • These signals can then be digitised and used by a computer • There are a huge range of sensors used to measure: • heat • light; • Sound • Movement etc, etc, etc…

17. Magnetic strip reader • Used to read data from a magnetic strip • Thin strips of magnetic tape - usually found on the back of plastic credit and debit cards. • When the card is inserted into a reader (in an Automatic Teller Machine or ATM for example) the tapes slides past a playback head similar to that used in a tape recorder. • This reads the data from the stripe and passes it to a computer.

18. Smart Card (Chip & Pin) • Data stored on an embedded micro processor. • Can store much more than a magnetic strip card. • More secure because it doesn’t just rely on a signature.

19. Input Devices and Methods • Objectives: • To understand what input devices are. • Identify their individual uses • Be able to identify the difference between manual and automated input devices.