CPU - KEYWORDS

Question 1

CPU

Answer 1

The purpose of the Central Process Unit is to fetch, decode and executes data. It carries out instructions of a computer and is often referred to as the brain of the Computer

Question 2

Cache

Answer 2

Cache is a high speed memory storage. It is used to store instructions/data that is frequently used. Data does not need to be fetched from RAM therefore it speeds up access

Question 3

Virtual Memory

Answer 3

A section of the hard disk is used to store items in RAM which are not being currently used .
It is used to allow more programs / data to be loaded when the RAM is insufficient

Question 4

This is the Memory Address Register. It is a very small area of memory that is used to hold a memory address. The memory address is provided by the Program Counter. The Memory Address is the next address in main memory to address.

Answer 4

MAR

Question 5

MDR

Answer 5

Once data is retrieved from Main Memory (RAM) it travels along the Data Bus to the Memory Data Register. Data/Instructions are held in the MDR temporarily. Any instructions will then be passed to the CIR.

Question 6

CIR

Answer 6

The CIR is the Current Instruction Register. This hold the instruction that has just been fetched from main memory and is about to be executed. The Current Instruction is split into an Op Code (the operation to be performed) and the Operand (the data in which to perform the operation on).

Question 7

All data and instructions currently in use are held here. When the power is turned off, all data/instructions are lost. (Volatile Memory)

Answer 7

RAM

Question 8

Carries addresses from the Processor (MAR) to Main Memory

Answer 8

Address Bus

Question 9

Data Bus

Answer 9

Carries Data/Instructions from Main Memory back to the Processor (MDR)

Question 10

Accumulator

Answer 10

The Accumulator is used to hold the result of a calculation or an operation. When a value is inputted into the computer it will be held in the accumulator. If a value is added – then the result is temporarily held in the accumulator.
The Accumulator is another Register.

Question 11

Hold the address of the next instruction that will be fetched.

Answer 11

PC (Program Counter)

Question 12

Performs arithmetic (Add / Subtract) and logical (AND, OR) operations

Answer 12

Arithmetic Logic Unit - ALU

Question 13

Secondary Storage

Answer 13

non-volatile storage of data/files