Unit 1.1 Systems Architecture

Question 1

What is a General Purpose Computer?

Answer 1

A computer designed to carry out various tasks
A computer that can have many applications
(Applications = tasks)

Question 2

Name 5 things that a general purpose computer can be used for

Answer 2

access the internet
browse the world wide web
use word processing software
play games
communicate via email and social media
design and build web pages
store and retrieve data
play videos and music

Question 3

Name 2 examples of a general purpose computer:

Answer 3

tablets - like PCs, they can run a variety of applications
smartphones - today’s smartphones can also run a variety of applications
games consoles - as well as games, modern consoles also allow users to watch videos, play music and browse the internet
media systems in cars - allow users to navigate, listen to music and connect to a smartphone

Question 4

What does a general purpose computer consist of?
A) Hardware
B) Software
C) All of the above

Answer 4

C) General purpose computers consist of both hardware and software.

Question 5

What is the difference between hardware and software?

Answer 5

Hardware is tangible/physical components of the computer e.g. Mouse, keyboard, monitor etc. ; Software is the programs that run on the computer

Question 6

Name one example of hardware

Answer 6

CPU, Hard disk, monitor, keyboard, mouse

Question 7

Name two examples of software

Answer 7

Windows, MACOS, IOS,

Question 8

How does a General purpose computer function?

Answer 8

The CPU receives instructions and data from an input or memory. The instructions and data are processed by the CPU and the results are either sent to an output or transferred to secondary storage.

Question 9

In the general purpose computer, where is the input and output from?

([https://www.bbc.co.uk/bitesize/guides/zbfny4j/revision/1]to see the diagram corresponding to the question)

Answer 9

The input is from the input device and the output is from the output device

Question 10

What is the purpose of the CPU?

Answer 10

to process data and instructions
to control the rest of the computer system
All programs and data processing are run in the CPU and all hardware components are, to some extent, controlled by it.

Question 11

What are the six main components of the CPU?

Answer 11

control unit (CU)
arithmetic logic unit (ALU)
registers
cache
buses
clock

Question 12

Name a function of the Control Unit (CU)

Answer 12

it fetches, decodes and executes instructions
it issues control signals that control hardware
it moves data around the system

Question 13

Name a function of the Arithmetic Logic Unit (ALU)

Answer 13

• It performs arithmetic and logical operations (decisions).
• Where calculations are done and where decisions are made.
• It acts as a gateway between primary memory and secondary storage . Data transferred between them passes through the ALU.

Question 14

Define a register

Answer 14

Registers are small amounts of high-speed memory contained within the CPU.

Question 15

Name two functions/uses of the register:

Answer 15

They are used by the processor to store small amounts of data that are needed during processing, such as:

the address of the next instruction to be executed
the current instruction being decoded
the results of calculations

Question 16

Name 5 different types of registers:

Answer 16

program counter
memory address register (MAR)
memory data register (MDR)
current instruction register (CIR)
accumulator (ACC)

Question 17

Define Cache

Answer 17

Cache is a small amount of high-speed random access memory (RAM) built directly within the processor.

Question 18

What is Cache used for?

II) What is the impact of this function?

Answer 18

It is used to temporarily hold data and instructions that the processor is likely to reuse.

II) This allows for faster processing as the processor does not have to wait for the data and instructions to be fetched from the RAM.

Question 19

What is the clock’s function?

Answer 19

The CPU contains a clock which is used to coordinate all of the computer’s components.

Question 20

Define Clock speed

Answer 20

The clock sends out a regular electrical pulse which synchronises (keeps in time) all the components. The frequency of the pulses is known as the clock speed.

Question 21

What is clock speed measured in?

Answer 21

Hertz (Hz),GigaHertz (GHz)

Question 22

True or false?

The higher the frequency, the more instructions can be performed in any given moment of time.

Answer 22

True

Question 23

Define a bus

Answer 23

A bus is a high-speed internal connection

Question 24

Name the function of a bus

Answer 24

Buses are used to send control signals and data between the processor and other components.

Question 25

What are the three types of bus?

Answer 25

Address bus, control bus and data bus

Question 26

True or false:

Von Neumann architecture is the design upon which many embedded system computers are based.

Answer 26

False, General purpose computers are based on Von Neumann architecture

Question 27

Name two key elements of Von Neumann architecture

Answer 27

• data and instructions are both stored as binary digits
• data and instructions are both stored in primary memory
• instructions are fetched from memory one at a time and in order (serially)
• the processor decodes and executes an instruction, before cycling around to fetch the next instruction

-the cycle continues until no more instructions are available

Question 28

Define the program counter

Answer 28

program counter - holds the memory address of the next instruction to be fetched from primary memory

Question 29

Define the Memory Address Register (MAR)

Answer 29

Memory Address Register (MAR) - holds the address of the current instruction that is to be fetched from memory, or the address in memory to which data is to be transferred

Question 30

Define the Memory Data Register (MDR)

Answer 30

Memory Data Register (MDR) - holds the contents found at the address held in the MAR, or data which is to be transferred to primary memory

Question 31

Define the Current Instruction Register (CIR)

Answer 31

Current Instruction Register (CIR) - holds the instruction that is currently being decoded and executed

Question 32

Define the Accumulator (ACC)

Answer 32

An accumulator is primarily used as a register in a CPU to store intermediate logical or arithmetic data in multistep calculations.

Question 33

What are the three factors that affect the CPU?

Answer 33

Clock speed
No. of cores
Cache size

Question 34

Define cores

Answer 34

A processing unit within a CPU is known as a core.

Question 35

True or false:

Each core is capable of fetching, decoding and executing its own instructions.

Answer 35

True

Question 36

True or false?

The less cores a CPU has, the greater the number of instructions it can process in a given space of time.

Answer 36

False, The more cores a CPU has = the more instructions that can be processed

Question 37

Define an embedded system

Answer 37

An embedded system is a small computer that forms part of a larger system, device or machine.

Question 38

What is the purpose of an embedded system?

Answer 38

Its purpose is to control the device and to allow a user to interact with it.

Question 39

Does an General purpose system tend to have one, or a limited number of tasks that they can perform?

Answer 39

No, an embedded system does, but a General purpose system can preform various tasks

Question 40

Name 3 examples of an embedded system

Answer 40

central heating systems
engine management systems in vehicles
domestic appliances, such as dishwashers, TVs and digital phones
digital watches
electronic calculators
GPS systems
fitness trackers

Question 41

True or false?

Embedded devices are usually programmable by a user.

Answer 41

False, embedded systems are not usually programmable by a user – the programming is usually done beforehand by the manufacturer.

(However, it is often possible to upgrade the software on an embedded device. For example, fitness trackers are embedded systems, but the software can often be upgraded by connecting the device to a PC and installing the new software.)

Question 42

Name 2 advantages of an Embedded system

Answer 42

Cheaper than GPS

Easier to build than a GPS