Electronic devices commonly use input, processor and output components according to their requirements. These components work together to receive information, process it and produce a result.

 Input devices

An input device is a device or component that provides information to an electronic system. It converts information or changes in the surroundings into a signal that can be processed by the system.

Examples include:

• Keyboard: Enters letters, numbers and commands into a computer.

• Mouse: Provides information about movement and selections.

• Joystick: Supplies directional control signals.

• Microphone: Converts sound into an electrical signal.

• Barcode reader: Reads barcode information and sends it to a computer.

• Stylus or pen input: Allows information to be entered by writing or drawing on a compatible device.

• Web camera: Captures images and video and supplies them to a computer.

• Touchscreen: Detects the user’s touch and sends the selected input to the system.

• Temperature or light sensor: Detects changes in the surroundings and sends corresponding signals to an electronic circuit.

Input devices allow users or the environment to communicate information to an electronic system.

Processor

A processor is the component that processes input information according to a program or set of instructions. It controls the operations of an electronic system and determines what action should be performed.

A computer’s Central Processing Unit (CPU) is an important example of a processor. It processes data and instructions, performs calculations and controls computer operations.

Processors may be found in computers, digital devices and automatic control systems. For example, a processor in an automatic lighting system can receive a signal from a sensor and decide whether the light should be switched on or off.

The processor acts as the decision-making part of an electronic system.

 Output devices

An output device is a device that receives processed information from an electronic system and presents the result in a useful form. Output may be visual, audible or mechanical.

Examples include:

• Monitor: Displays text, pictures, videos and other processed information.

• Printer: Produces a hard copy of information on paper.

• Speakers: Convert electrical signals into sound.

• Headphones: Allow a user to hear sound privately.

• Projector: Displays images and information on a large screen.

• Buzzer: Produces sound as an alert or warning.

• LED or lamp: Produces light when activated by a circuit.

• Motor: Produces movement when supplied with electrical energy.

Output devices allow the results of processing to be communicated to users or used to control equipment.

How input, processor and output work together

Consider an automatic school bell system.

1. Input: A clock circuit supplies a signal when the scheduled time is reached.

2. Processor: The control circuit checks the signal and determines whether the bell should operate.

3. Output: The circuit activates a buzzer or bell to produce sound.

The same general arrangement is used in many electronic systems. A sensor can provide input, a control circuit or processor can process the signal, and an output component can operate a light, alarm, motor or display.

Uses in schools and surroundings

Input, processor and output components are used in many familiar devices:

• In a computer, the keyboard and mouse provide input, the CPU processes information, and the monitor and printer provide output.

• In an automatic security alarm, a sensor detects an event, the control circuit processes the signal, and a buzzer produces an alert.

• In an automatic light, a light sensor provides input, the control circuit responds to the signal, and a lamp produces light.

• In a digital thermometer, a sensor detects temperature, the electronic circuit processes the measurement, and the display shows the temperature.

These examples show how electronic components work together to perform useful tasks in schools, homes and workplaces.