1.1.2 - Types of Processor

• Complex Instruction Set Computer (CISC)

  • large instruction set
  • instructions built into hardware
  • originally used as standard, then replaced with RISC design
  • more used in microcontrollers and embedded design
• Reduced Instruction Set Computer (RISC)

  • small instruction set
  • each instruction is approx. one line of machine code
  • takes one clock cycle
• RISC Processors

  • compiler has to do more work to translate high level code into machine code
  • more RAM required to store code
  • pipelining is possible since each instruction takes one clock cycle
• CISC Processors

  • compiler has less work to translate high level code into machine code
  • less RAM required as code is shorter
  • many specialised instructions are made, even though few are used
• Multi-core CPUs

  • have multiple independent cores that can complete instructions separately, resulting in higher performance
• Parallel Systems

  • accomplish similar task to multi-core CPUs but can complete tasks with a single core by using threading
• Multi-Core CPUs vs Parallel Systems

  • multi-core systems generally perform better in larger projects than parallel systems
• Co-Processors

  • a secondary processor designed to supplement activities of the primary processor
• Graphics Processing Unit (GPU)

  • has lots of independent processors, unlike CPUs, which work in parallel
  • very efficient at completing repetitive tasks such as image processing and machine learning
  • a type of co-processor
• Co-Processor

  • secondary processor designed to supplement activities of primary processor