The CPU

• What does CPU stand for?

  Central Processing Unit
• What factors influence the processing power of a CPU?

  Clock speed, number of cores, cache size
• What are the two main types of CPU architecture?

  Von Neumann and Harvard
• What are the three main parts of the CPU?

  • Control Unit (CU)
  • Arithmetic Logic Unit (ALU)
  • Cache
• What is the main job of the Control Unit (CU)?

  Manage fetching, decoding, and execution
• What does the Control Unit control within the CPU?

  Flow of data inside and outside the CPU
• What does the Arithmetic Logic Unit (ALU) do?

  Performs calculations and logic operations
• What types of operations can the ALU perform?

  Addition, subtraction, comparisons, logic operations
• How does the cache compare to RAM?

  Faster than RAM but has lower capacity
• Which cache level is the quickest?

  L1
• What is the role of registers in the CPU?

  Temporarily hold tiny bits of data
• What is the function of the program counter (PC)?

  Holds the memory address of the instruction
• What does the memory address register (MAR) hold?

  Memory address about to be used
• What does the accumulator do?

  Stores intermediate results of calculations
• What does the memory data register (MDR) hold?

  Actual data or instruction fetched from memory
• What is the Fetch-Execute Cycle?

  1. Fetch instruction from memory
  2. Decode instruction
  3. Execute instruction
• What happens during the FETCH phase of the Fetch-Execute Cycle?

  Copy address to MAR, fetch instruction to MDR
• What occurs during the EXECUTE phase of the Fetch-Execute Cycle?

  Instruction is performed by the CPU
• What does the Control Unit do during the DECODE phase?

  Decodes the instruction in the MDR
• How does the Von Neumann architecture function?

  • CPU runs programs stored in memory
  • Programs consist of instructions and data
  • Uses one memory for both data and instructions
• When was the Von Neumann architecture designed?

  In 1945
• What is a key feature of the Von Neumann architecture?

  Uses one memory for data and instructions
• What does the program counter (PC) do in the Fetch-Execute Cycle?

  Holds the memory address of the instruction
• What is the role of the memory address register (MAR) in the CPU?

  Holds the memory address about to be used
• What is the purpose of the accumulator in the ALU?

  Stores intermediate results of calculations