System architecture

• What does CPU stand for?

  Central Processing Unit
• Why is it a common mistake to think the 'C' in CPU stands for computer?

  Because many people are not aware that it stands for central.
• What is the fetch-decode-execute cycle?

  It is a process that the CPU performs billions of times to execute instructions.
• From where can the CPU receive instructions?

  From input devices or program instructions.
• What does RAM stand for?

  Random Access Memory
• How does the CPU interact with RAM?

  The CPU fetches instructions from RAM during the fetch-decode-execute cycle.
• What does the 'F' in the fetch-decode-execute cycle represent?

  Fetching instructions from memory.
• What does the 'D' in the fetch-decode-execute cycle represent?

  Decoding the fetched instruction.
• What does the 'E' in the fetch-decode-execute cycle represent?

  Executing the decoded instruction.
• What are the three C's that affect CPU performance?

  Clock speed, cores, and cache.
• How is clock speed measured?

  In hertz, often in gigahertz.
• What does a clock speed of 3.5 gigahertz mean?

  It means the CPU can perform 3.5 billion instructions per second.
• How does having multiple cores affect CPU performance?

  Each core can work independently, allowing for more instructions to be processed simultaneously.
• If a CPU has a clock speed of 3.2 gigahertz and is dual-core, what is its potential instruction processing capability?

  6.4 billion instructions per second.
• If a CPU has a clock speed of 3.5 gigahertz and is quad-core, what is its potential instruction processing capability?

  14 billion instructions per second.
• What is the role of cache in CPU performance?

  Cache holds frequently used instructions for faster access than main memory.
• What can too much cache lead to in CPU performance?

  It can be detrimental to overall performance.
• What is an embedded system?

  It is a system built into a larger machine for a specific purpose.
• How does an embedded system differ from a general-purpose computer?

  An embedded system is built for one purpose, while a general-purpose computer can run multiple programs.
• What is the input-process-output model in computing?

  It describes how a computer takes in data, processes it, and outputs results.
• What is a common example of an embedded system?

  A washing machine.
• What components are typically found in an embedded system?

  All components are usually built into a single circuit board.
• What is the role of buttons on a washing machine in relation to its embedded system?

  They interact with the circuit board to control functions like starting or canceling a wash.
• What is the first part of the CPU that manages the fetch-decode-execute cycle?

  The control unit.
• What does the control unit do in the CPU?

  It manages the fetching, decoding, and executing of instructions.
• What is the function of the arithmetic logic unit (ALU)?

  It performs calculations and logic operations.
• What does ALU stand for?

  Arithmetic Logic Unit
• What is the role of the accumulator in the ALU?

  It stores the results of calculations performed by the ALU.
• What does cache store?

  Frequently used instructions.
• How does the CPU check for data in cache?

  The CPU checks cache before fetching from RAM.
• What are the different levels of cache?

  Level 1 is the fastest but has the least storage, followed by Level 2 and Level 3.
• What is von Neumann architecture?

  It is a system where the CPU runs programs stored in memory.
• What does the program counter do in von Neumann architecture?

  It keeps track of the current instruction being executed.
• What does the memory address register do?

  It holds the address of the instruction to be fetched from memory.
• What is the role of the memory data register?

  It stores the instruction fetched from memory.
• What happens during the execution part of the fetch-decode-execute cycle?

  The control unit decodes the instruction and the ALU performs any necessary calculations.
• How does the fetch-decode-execute cycle repeat?

  The program counter is incremented, and the cycle starts again with the next instruction.
• Why is repetition important in learning about the CPU?

  It helps embed knowledge about the different registers and their purposes.
• What should students do when practicing example questions about the CPU?

  They should try not to look back at their notes and check their answers afterward.