Architecture

Question 1

Define a CPU (3)

Answer 1

acts as brain of computer

is a microprocessor/processor

executes all instructions in computer application

Question 2

Function of ALU

Answer 2

carries out arithmetic/logic operations while program being run

Question 3

Purpose of RAM

Answer 3

holds all data/programs that need to be accessed by CPU

Question 4

Function of CIR

Answer 4

stores current instruction being decoded/executed

Question 5

Function of ACC (2)

Answer 5

carries ALU calculations

stores data temporarily during those calculation

Question 6

Function of MAR

Answer 6

stores address of memory location currently being read from/written to

Question 7

Function of PC

Answer 7

stores address where next instruction to be read can be found

Question 8

Define a control bus (3)

Answer 8

Carries signals to other components of CPU

directs CPU

unidirectional or bidirectional

Question 9

Define Cache memory (4)

Answer 9

temporary memory using static RAM

located within CPU

stores frequently used instructions

stores data that needs to be accessed faster

Question 10

Define a data bus (2)

Answer 10

Carries data being processed

Data travels in both directions (bi-directional)

Question 11

Define an address bus (2)

Answer 11

carries address locations of next item to be fetched

data travels one way ( unidirectional)

Question 12

Name the registers (5)

Answer 12

Program Counter (PC)

Memory Address Registers (MAR)

Memory Data Register (MDR)

Current Instruction Register (CIR)

Accumulator (ACC)

Question 13

Function of control unit (4)

Answer 13

controls operation of memory, processor and input/output

fetches each instruction in turn

interprets instructions

sends signals to other components telling them what to do

Question 14

Describe the fetch decode execute cycle (7)

Answer 14

PC has address of next instruction to fetch

address in PC copied to MAR via address bus

instruction copied from MAR to MDR

instruction copied from MDR to CIR

value in PC incremented by 1 to point at next instruction to fetch

address of instruction placed in MAR

instruction decoded/executed by sending signals via control bus to computer components

Question 15

Factors which determine the performance of the CPU (4)

Answer 15

clock speed

width of address/data bus

cache

size of core

Question 16

Define a core

Answer 16

made up of ALU, control unit, registers

Question 17

Define an opcode

Answer 17

informs CPU what operation needs to be done

Question 18

Define an operand (2)

Answer 18

data which needs to be acted on

register in memory

Question 19

Purpose of operation

Answer 19

instruct ALU and CU

Question 20

What is an operation made up of (2)

Answer 20

operand

opcode