System Architecture Flashcards
(50 cards)
the purpose of the CPU
What is the purpose of the CPU?
The purpose of the Central Processing Unit (CPU) is to fetch, decode and execute instructions.
What role does the CPU play in a computer?
The CPU is the brain of the computer; it takes an input, processes data, and produces an output.
What is the Fetch-Execute Cycle?
The Fetch-Execute Cycle is the cycle that the CPU runs through billions of times per second to make a computer work.
What are the stages of the Fetch-Execute cycle?
- Fetch stage
- Decode stage
- Execute stage
What happens during the fetch stage of the Fetch-Execute cycle?
The next instruction or data must be fetched from the computer’s memory (RAM) and brought back to the CPU.
What occurs during the decode stage of the Fetch-Execute cycle?
The CPU needs to work out what is required from the instruction, which could involve a range of tasks.
What is executed during the execute stage of the Fetch-Execute cycle?
The CPU carries out the instruction that was fetched, which may include:
* Performing a calculation
* Storing a result or data back in main memory (RAM)
* Going to main memory to fetch data from a different location
True or False: The Fetch-Execute Cycle repeats billions of times per second.
True
Fill in the blank: The CPU fetches an instruction or data from _______.
[memory]
What is the output of the CPU after processing an input?
The output is delivered to the user.
What is an example of input in the Fetch-Execute cycle?
Clicking a button on the gamepad.
What is an example of output in the Fetch-Execute cycle?
The player moving on screen.
CPU components
What are the components of the CPU?
The CPU is made up of 4 key components:
* Arithmetic Logic Unit (ALU)
* Control Unit (CU)
* Cache
* Registers
Each of the components sits within the CPU.
What is the function of the Arithmetic Logic Unit (ALU)?
Performs arithmetic operations and logical decisions
Example of logical decision: IF X > 5 THEN DO ……….
What is the function of the Control Unit (CU)?
Coordinates how data moves around the CPU by sending signals to control the flow of the data and decodes instructions fetched from memory.
What is the function of the Cache in the CPU?
Very small, very fast memory used to provide quick access to frequently used instructions and data, which speeds up CPU performance.
How does Cache improve CPU performance?
Prevents the CPU from having to repeatedly fetch frequently used instructions from RAM.
What are Registers in the CPU?
Extremely small, extremely fast memory located in the CPU, each with a specific purpose.
What is the Von Neumann architecture?
The Von Neumann Architecture is a design of the CPU proposed by Mathematician John Von Neumann in the 1940s, which most general-purpose computers are built upon.
What components does the Von Neumann Architecture outline?
It outlines how the computer memory, input/output devices, and processor work together.
How many main registers are in the Von Neumann Architecture?
4 main registers.
What is the acronym for the Program Counter?
PC.
