Back to: Computer Science Course GCE A Level Cameroon
Input devices in computer science – GCE A level Cameroon Lesson
I. INPUT DEVICES
Topic: Input devices in computer science – GCE A level Cameroon Lesson. An input device can be defined as an electromechanical device that allows the user to feed data into the computer for analysis and storage, and to give commands to the computer. The computer accepts input in two ways; manually and directly. In the case of manual data entry, the user enters the data into the computer by hand, for example, by using the keyboard and the mouse. kamerpower.com
A user can also enter the data directly by transferring information automatically from a source document (like from check using MICR) into the computer. Some of the commonly used input devices are keyboard, pointing devices like mouse and joystick, speech recognition system, digital camera, scanners and so on.
I.1 Keyboard
A keyboard is the most common data entry device. The keyboard is designed like a regular typewriter with a few additional keys. The data are entered into the computer by using various keys.
There are different types of keyboard layouts such as QWERTY, DVORAK and AZERTY, but the most common layout is the QWERTY.
Working of a Keyboard
At its essence, a keyboard consists of a series of switches connected to a small keyboard microprocessor that monitors the state of each switch and initiates a specific response to a change in that state. When the user presses a key, it causes a change in the amount of current flowing through the circuit associated specifically with that key. The keyboard microprocessor detects this change in the current flow.
