Computer Architecture

• What is the CPU?

  • This is the Central Processing Unit
  • It continuously processes instructions and data
  • The data is inputted by the fetch-decode-execute cycle
  • The CPU contains the Arithmetic Logic Unit (ALU) and Control Unit (CU)
• What is the fetch-execute-decode cycle?

  This is where instructions are fetched from the RAM and then decoded by the Control Unit to find out what to do with it. The instructions are then executed. The cycle is then repeated
• What are the CPU components?

  • ALU (Arithmetic Logic Unit)
  • CU (Control Unit)
  • Clock
  • Registers
  • Data, addresses, and control buses
• What is the purpose of the ALU?


  This carries out mathematical and logical operations, such as AND, OR and NOT and binary shifts.
• What registers are in the ALU?

  Accumulator and Memory Data Register
• What is the purpose of the CU?

  This coordinates all the CPU's actions in the fetch-execute-decode cycle and decodes the instructions. It sends and receives control signals to fetch and write data.
• What registers does the CU have?

  Program Counter, Memory Address Register, and Current Instruction Register
• What is the purpose of the clock in the CPU?

  Regulates the speed and timing of all the signals and computer functions
• What are registers in the CPU?

  Temporary storage locations for memory, instructions or data. They are used for the fetch-decode-execute cycle for specific purposes
• What types of buses are there in a CPU?

  Address, control and data
• What are buses in the CPU?

  They are wires which transfer data, instructions, memory addresses and control signals from one component to the other.
• What is the advantage of having a dual-core CPU?

  It can process two instructions simultaneously, increasing the performance
• What are the registers in the CPU?

  • Program Counter (PC)
  • Memory Address Register (MAR)
  • Current Instruction Register (CIR)
  • Accumulator (ACC)
• What are the features of Von Neumann's Architecture?

  • Data and instructions are stored in the RAM as binary
  • A CPU fetches instructions from memory and executes them one at a time
• What is the Accumulator?


  A register which stores the results of the calculations carried out by the ALU
• What is the Current Instruction Register?

  A register that stores the instructions the CPU is currently decoding or executing
• What is the Program Counter?

  A register that stores the address of the next instruction to be fetched.
• What is the Memory Address Register?


  This is a register that stores the address of the instructions or data to be fetched or written to the memory
• What does the Memory Data Access do in the CPU?

  Stores data or a program instruction when it is fetched from memory or data that is waiting to be written to memory
• What can improve the performance of the CPU?

  • Multiple cores
  • More cache
  • A faster clock speed
• How can cache improve the performance of the CPU?

  As the cache is used for storing frequently used data and is used in the fetch-execute-decode cycle, by increasing it more data can be stored and can be processed faster
• How can clock speed improve the performance of the CPU?

  A faster clock speed will increase the number of fetch-execute-decode cycles per second
• How can cores improve the performance of the CPU?

  The more cores in a computer, the more instructions can be processed per second
• What is clock speed?

  How many instructions the core can execute per second
• What is cache?


  Memory used for storing frequently used instructions or data, recently used instructions and instructions that are to be fetched and executed next in the process
• What does a core do in the CPU?

  It processes information and carries out the fetch-decode-execute cycle