Embedded Systems & General Purpose Computers

General Purpose Computers

  • Designed to perform many different tasks.
  • Can run multiple applications (internet, word processing, games, media, communication).
  • Typical examples:
    • Desktop / laptop PC
    • Tablet
    • Games console
    • Smart phone
    • In-car media / infotainment systems

Embedded Systems

  • Computer system inside a larger electrical or mechanical device.
  • Dedicated function: controls the host device & enables user interaction.
  • Usually stored on ROM; runs a fixed program.
  • Common examples:
    • Washing machine, dishwasher, microwave
    • MP3 player, digital clock / watch, fitness tracker
    • Traffic-light controller
    • Burglar alarm, autopilot, GPS unit

Characteristics of Embedded Systems

  • Low power consumption (often battery-powered)
  • Small physical size
  • Low unit cost (limited functions → cheaper hardware & simpler software)
  • High reliability (few tasks → fewer faults)

Benefits vs General Purpose Computers

  • Smaller → devices can be more compact
  • Cheaper to manufacture → lowers product price
  • More reliable → less likely to fail
  • Lower power use → energy efficient / longer battery life

Quick Knowledge Check (self-test)

  • Definition recap:
    • General purpose computer: "designed to carry out many tasks"\text{"designed to carry out many tasks"}
    • Embedded system: "dedicated computer within a larger system"\text{"dedicated computer within a larger system"}
  • Give 2 examples of each type.
  • List 2 characteristics of embedded systems.
  • Explain 1 benefit of using an embedded controller in a microwave instead of a PC.