Ch. 1 — Data Representation
1.1 Number Systems 1.2 Text, Sound & Images 1.3 Data Storage & Compression
Ch. 2 — Data Transmission
2.1 Data Transmission 2.2 Error Checking 2.3 Encryption
Ch. 3 — Hardware
3.1 Computer Architecture 3.2 Input & Output Devices 3.3 Data Storage 3.4 Network Hardware
Ch. 4 — Software
4.1 Types of Software & Interrupts 4.2 Programming Languages & IDE
Ch. 5 — The Internet
5.1 Internet & World Wide Web 5.2 Digital Currency 5.3 Cyber Security
Ch. 6 — Emerging Tech
6.1 Automated Systems 6.2 Robotics 6.3 Artificial Intelligence
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Chapter 2
Chapter 3
Chapter 4
Chapter 5
Chapter 6
Home/ Paper 1/ 3.2 Input and Output Devices
3.2

3.2 Input and Output Devices

Hardware devices used to provide data to and receive information from a computer.

Input Devices

  • Hardware device used to provide data and control signals to a computer

Common input devices

  • Barcode Scanner
  • Digital Camera
  • Microphone
  • Optical Mouse
  • QR Scanner

Advantages of using QR Codes in a Supermarket

  • No need to price each item individually
  • Automatic stock control
  • Faster checkouts as items are immediately scanned
  • Fewer errors in bills

Uses of digital cameras

  • Reading QR codes on a smartphone
  • Video conferencing
  • Robots, where information about surroundings is needed

Output Devices

  • Hardware devices that allow information to be sent out of a computer system

Common output devices

  • Actuators
  • Inkjet, Laser, 3D printer
  • LED, LCD screen
  • Speaker

DLP Advantages

  • Higher contrast ratios
  • Greater longevity
  • Quieter running

DLP Disadvantages

  • The image tends to suffer from “shadowing” during moving images
  • They do not have grey components in the image
  • Colour definition is not as good as LCD projectors

Printers

Inkjet Printer Pros & Cons

  • Produce high-quality photo/vivid colour images
  • Do not need to warm up
  • Very low purchase price compared to laser printers
  • Have a small ink reservoir
  • Not suitable for long print runs (ink cartridges can be used up quickly)
  • Small paper trays
  • Slower prints per minute compared to laser

Laser Printer Pros & Cons

  • Have large paper trays for long print runs
  • Have large capacity toner cartridges
  • Very quiet printing
  • Cost per page is very low
  • Expensive to maintain (toner is expensive)
  • Not suitable for printing high quality pictures
  • High up front cost (compared to inkjet)

Uses of a 3D Printer

  • Prosthetic Limbs
  • Making prototypes
  • Fashion and art

Which printer?

  • Laser printer: high volume printouts
  • Inkjet printer: high quality image printouts
  • 3D printer: printing models/prosthetics

Sensors

  • Acoustic — measures the level of sound in an environment
  • Accelerometer — measures the acceleration forces
  • Flow — measures the amount of liquid or gas flowing through or around an environment
  • Gas — measures the presence and concentration of a gas in the atmosphere
  • Humidity — measures the level of moisture in the atmosphere
  • Infra-red — measures infra-red radiation
  • Level — measures whether a substance such as a liquid is at a certain level or amount
  • Light — measures the ambient light in a certain environment
  • Magnetic field — measures the presence of magnetic field that may be emitted by an object
  • Moisture — measures the amount of water that is present in a substance
  • pH — measures the pH level of a substance
  • Pressure — measures the force of pressure that is applied to the sensor or device
  • Proximity — measures how close an object is in comparison to the sensor
  • Temperature — measures the temperature of an object or substance