Component 1 Section 1 Flashcards
(34 cards)
What is the purpose of the CPU?
The central processing unit (CPU) executes instructions in computer programs. It is responsible for fetching, decoding, and executing instructions and controlling the operation of all hardware components.
Name the three main components of the Von Neumann architecture.
- CPU (Central Processing Unit), 2. Memory, 3. Input/Output devices connected by buses
What is the function of the ALU in a CPU?
The Arithmetic Logic Unit (ALU) performs all arithmetic operations (addition, subtraction, etc.) and logical operations (AND, OR, NOT, etc.) within the CPU.
What is the function of the CU in a CPU?
The Control Unit (CU) controls the flow of data within the CPU, decodes instructions, and sends signals to other parts of the CPU and memory to execute instructions.
What are registers and what is their purpose?
Registers are small, high-speed memory units within the CPU that temporarily hold data and instructions that the CPU is processing. They allow for quick access to frequently used data.
What does the Program Counter (PC) register do?
The Program Counter holds the memory address of the next instruction to be fetched from memory.
What is the function of the Memory Address Register (MAR)?
The MAR holds the memory address of data that needs to be accessed (read from or written to).
What is the function of the Memory Data Register (MDR)?
The MDR temporarily holds data being transferred to or from memory.
What does the Accumulator register do?
The Accumulator is a register that holds the results of calculations performed by the ALU.
What is clock speed and how is it measured?
Clock speed is the number of pulses per second generated by the CPU’s internal clock. It is measured in Hertz (Hz), typically Gigahertz (GHz). Higher clock speeds generally allow for faster execution of instructions.
What is the Fetch-Execute cycle (also known as the Fetch-Decode-Execute cycle)?
The continuous process by which a CPU loads instructions from memory, determines what they are asking the computer to do, and then carries them out.
What are the stages of the Fetch-Execute cycle?
- Fetch: Get instruction from memory, 2. Decode: Determine what the instruction is asking the CPU to do, 3. Execute: Carry out the instruction, 4. Store: Save the result if needed
What does CPU cache do and why is it important?
CPU cache is a small, fast memory located on or close to the CPU that stores frequently accessed data. It’s important because it reduces the time needed to access data from the main memory, improving overall system performance.
What is the difference between L1, L2, and L3 cache?
L1 cache is smallest but fastest and closest to the processor core. L2 is larger but slower than L1. L3 is larger still but slower than L2 and often shared between multiple cores.
What factors affect CPU performance?
- Clock speed, 2. Number of cores, 3. Cache size, 4. Architecture design, 5. Word length/data width
What is a core in a CPU?
A core is a processing unit within a CPU that can execute instructions independently. Modern CPUs often have multiple cores to perform parallel processing.
What is the benefit of having multiple cores in a CPU?
Multiple cores allow for parallel processing, where multiple instructions can be executed simultaneously, improving performance for multi-threaded applications and multitasking.
What is meant by the term ‘embedded system’?
An embedded system is a computer system with a dedicated function within a larger mechanical or electrical system, often with real-time computing constraints.
Give three examples of embedded systems.
- Smart thermostats, 2. Digital watches, 3. Car engine control systems, 4. Automatic washing machines, 5. Traffic lights
What is RAM and what is its purpose?
Random Access Memory (RAM) is volatile memory that temporarily stores data that the CPU needs to access quickly. It loses its contents when power is turned off.
What does it mean that RAM is ‘volatile’?
Volatile means that data stored in RAM is temporary and is lost when the computer is powered off or restarted.
What is the difference between RAM and ROM?
RAM (Random Access Memory) is volatile and can be written to and read from. ROM (Read-Only Memory) is non-volatile and can only be read from, not written to under normal operation.
What is the purpose of ROM in a computer?
ROM stores the essential startup instructions (bootstrap) needed for the computer to start, including the BIOS or UEFI firmware.
What is virtual memory?
Virtual memory is a memory management technique that uses part of the hard disk to simulate additional RAM, allowing a computer to run programs larger than its physical RAM.
