4.4 Computer Componenets

Question 1

Components of Von Neumann Architecture:

Answer 1

ALU (Arithmetic and Logic Unit)

Control Unit (CU)

Registers

Question 2

ALU:

Answer 2

Performs all of the arithmetic and logical operations of the CPU

Addition, Subtraction, etc/Comparisons/Boolean Operations

Question 3

Control Unit:

Answer 3

Sends out control signals to the other parts of the CPU

Executes program instructions by following the fetch/decode/execute cycle

Made up of : 
1. The clock 
– co-ordinates the CPU's activity 
2. The decoder 
– decodes program instructions

Question 4

Registers:

Answer 4

Tiny amounts of super-quick memory within the CPU

Used to hold information needed for the CPU to work

Each register holds a piece of information

Question 5

What are the 4 registers:

Answer 5

Program Counter (PC)

Memory Address Register (MAR)

Memory Data Register (MDR)

Accumulator (ACC)

Question 6

Program Counter:

Answer 6

Holds the memory of location address of the next instruction to be performed by the CPU

Question 7

MAR:

Answer 7

Holds address of the location in memory where data is to be retrieved or stored

Question 8

Accumulator:

Answer 8

Holds the result of the calculations and operations performed by the ALU

Question 9

MDR:

Answer 9

Holds the data that has been retrieved from memory, or that is about to be stored in memory

Question 10

Fetch:

Answer 10

1. Address of the next instruction to be processed is copied from the Program Counter to the MAR
2. The PC is incremented to point to the next instruction that will be needed when the cycle starts again
3. The instruction stored at the location held by the MAR is copied to the MDR

Question 11

Decode:

Answer 11

1. The Control Unit decodes the instruction and sends control signals to the component within or outside the CPU that needs to act

Question 12

Execute:

Answer 12

1. The operation indicated by the instruction is performed by the appropriate component

Question 13

Properties of Solid Storage:

Answer 13

High Speed
High Cost
Good Capacity
Good Reliability

Question 14

Properties of Magnetic Storage:

Answer 14

Good Reliability
Low Cost
Low Speed
High Capacity

Question 15

Properties of Optical Storage:

Answer 15

Low Cost
Great Reliability
Low Speed
Good Capacity

Question 16

Properties of cloud:

Answer 16

No upgrades 
Easy Access
Security
Pricing Changes
Risk of Privacy
Internet Connection required

Question 17

Application Software:

Answer 17

Helps a user of a computer system to complete a given task

Question 18

System Software:

Answer 18

Controls hardware of the computer and provides an environment for application to run

Question 19

Types of system software:

Answer 19

1. Operating Systems
2. Device Drivers
3. Utility Software

Question 20

Operating Software:

Answer 20

Manage access to the hardware in the computer

Question 21

Utility Software:

Answer 21

Performs maintenance tasks to make sure the operation of the system continues

Question 22

Device Drivers:

Answer 22

Small programs which tell the operating system how to use a piece of hardware

Question 23

Transistors:

Answer 23

Electrical components made from semiconductor materials that can act as electrically-controlled switches. They can be used to temporarily store data (for example in some forms of primary storage)

Question 24

Data Access in Solid Storage:

Answer 24

Data can be accessed randomly, This means that any piece of data can be accessed in a constant amount of time

This is achievable because there are no moving parts

Question 25

Data Access in Magnetic Storage:

Answer 25

Data could be stored anywhere on the disk, and so to read/write data we first need to find the location on the disk

A magnetic read/write head is used to access the data while the platter spins

Question 26

Data Access in Optical Storage:

Answer 26

A laser is shone on the disk surface

If the laser hits a pit, it is reflected elsewhere

If the laser hits a land, it will be reflect into a sensor

These can then be used to represent a 1 or 0

Question 27

Data Storage in Solid Storage:

Answer 27

Solid state drives are made of flash memory

Flash memory stores the value of each bit in semi-conductor chip

Question 28

Data Storage in Magnetic Storage:

Answer 28

The value of each bit of data (0 or 1) is represented as a positively or negatively charged magnetic particle

These particles are part of a magnetic disk called the platter

Question 29

Data Storage in Optical Storage:

Answer 29

Each 1 or 0 (value of a bit) is represented as a microscopic hole – called a pit- or a flat surface – called a land – on the surface of the dis