Components of the CPU

Question 1

Purpose of the CPU?

Answer 1

To execute instructions stored in memory by repeating the fetch execute cycle

Question 2

Purpose of the ALU? and what does it stand for?

Answer 2

Arithmetic Logic Unit. Carries out arithmetic and logic operations

Question 3

Purpose of CU? and what does it stand for?

Answer 3

Control unit. Coordinates the CPU’s actions in the fetch execute cycle

Question 4

Purpose of Cache? and typical size?

Answer 4

Up to 32MB. Sends and receives control signals from other devices in the computer to other devices in the computer

Question 5

Purpose of Registers? and typical size?

Answer 5

32 or 64 bits. Temporarily store instructions, addresses or data in the CPU

Question 6

Purpose of MDR (register)? and what does it stand for?

Answer 6

Memory data register. Holds data or a program instruction when it is fetched from memory or waiting to be written to memory

Question 7

Purpose of the Accumulator (register)?

Answer 7

A register where results of ALU operations are stored

Question 8

Purpose of PC (register)? and what does it stand for?

Answer 8

Program Counter. A register which holds the memory addresses of the next instruction to be processed

Question 9

Purpose of MAR (register)? and what does it stand for?

Answer 9

Memory address register. Holds the address of the current instruction or piece of data to be fetched or stored

Question 10

Name the 4 common registers in full

Answer 10

Memory address register
Memory data register
Accumulator
Program counter