Computers

Question 1

What is Vonn Neumann architecture/Stored program concept

Answer 1

Programs stored inside the computer that can be reprogrammed.

Question 2

CPU

Answer 2

Carries out program instructions and it does this using the FDE cycle.

Question 3

Processing unit

Answer 3

• an arithmetic logic unit
• processor registers

Question 4

Control unit

Answer 4

Receives signals from other parts of the computer system and sends signals to them,

Question 5

RAM

Answer 5

• Random Access Memory - Used to store data and machine code currently being used
• Volatile - data lost when turned off
• Stores programs and instructions.
• Read and Write
• 1-256GB

Question 6

ROM

Answer 6

Read-Only Memory
* Stores important system information and boot code.
* Volatile.
* 6-8MB

Question 7

Cache

Answer 7

High-speed memory used to store frequently accessed data or instructions. Located closer to the CPU than the main memory, allowing for faster access times and improving system performance

Stores frequently accessed data, e.g. A font, a texture pack

Question 8

FDE

Answer 8

Fetch
Decode
Execute

Question 9

Fetch

Answer 9

• the CPU fetches data and instructions from the RAM and saves it in its very short memory, called register.
• CPU uses the address bus. the memory address of the next item that the CPU wants is put on the address bus.data from this memory address travels from the RAM on another bus called the data bus.

Question 10

Decode

Answer 10

CPU working out what the instructions that it has just fetched actually mean.

Question 11

Execute

Answer 11

when the data processing happens
instructions are carried out on the data. some instructions are carried out by the ALU (adding, shifting, AND, OR)

Question 12

Contents of the CPU

Answer 12

• an instruction register
• a program counter
• memory that stores data + instructions
• external data storage
• input and output date

Question 13

What is a computer

Answer 13

• Anti malware
• Encryption
• Acceptable use policies
• Backup
• Recovery procedures

Question 14

Embedded system

Answer 14

An embedded system is a computer that has a specific function and does not do anything else

Small storage device to store simple programs, as it relies on fixed inputs and outputs. It needs no software updates.

Question 15

Uses of an embedded system

Answer 15

A traffic light

Switch lights, keep track of time, recieve input from pedestrian button, recieve input from road sensors

Question 16

Characteristics of an embedded system

Answer 16

• Task specific (single purpose)
• Low power consumption
• Small physical size
• Low maintenance
• Low cost per unit
• Less storage
• Limited user interface

Question 17

Purposes of an OS

Answer 17

Software that manages a computer’s hardware and software resources and providing common services for computer programs

Provides easy-to-use GUI (graphical user interface)

Question 18

Functionality of an OS

Answer 18

Input and output from peripherals

Providing user interface

File management
Program management
Memory management
Processor management

Running applications

Ensuring security
Error handling

Question 19

Utility software

Answer 19

• File repair
• Backup
• Data compression
• Defragmentation
  Backup
  Antivirus
  Firewall
  App update mangement
  Formatting disks and drives
  System analyis tools

Question 20

Characteristics of a general purpose computer

Answer 20

• Non task specific
• High power consumption
• Often large
• High cost

Question 21

Methods of identifying vulnerabilities

Answer 21

Audit trails
Code reviews

Question 22

ALU

Answer 22

Performs actual operations on data, arithmetic or relational.

Question 23

Registers

Answer 23

extremely fast memory. located on the processor, and very very small. (Bytes)
Faster than RAM as no buses needed

Question 24

Clock

Answer 24

determines the speed of the CPU.

the chip uses a vibrating quartz crystal that maintains a constant rate of vibration.

Question 25

Instruction register

Answer 25

holds instructions executed by CPU

Question 26

Accumulator

Answer 26

holds ALU vales

Question 27

Program counter

Answer 27

holds the memory address of the next instruction to be fetched

Question 28

Bus

Answer 28

A thin wire used to connect computer components and transfer data between them

Question 29

Data bus

Answer 29

Carries binary data from component to component Bidirectional

Question 30

Control bus

Answer 30

Carries signals that control CPU components Birdirectional

Question 31

Address bus

Answer 31

Carries the address of a memory location Unidirectional

Question 32

Interpreter

Answer 32

Transfers from high level to machine code line-by-line as the program runs

Question 33

Compiler

Answer 33

Translates from high level to machine code before the program runs

Question 34

High level programming languages

Answer 34

Easier for humans to use as the language is closer to English * - Abstracted away from hardware * - Uses English-like statements * - Requires a translator to convert source code to machine code * - Python, HTML, Java, C++

Question 35

Microprocessors

Answer 35

Each microprocessor with a unique set of components requires a different unique set of instructions. For each allowable and defined behaviour, there is an abstract instruction.

Question 36

Low level programming languages

Answer 36

Assembly and machine code are the **only** two low-level programming languages. * Sits close to hardware * Consists of mnemonics that represent binary code

Question 37

Machine code

Answer 37

**Binary patterns representing a program** * Simple for CPU to execute, difficult for humans to understand * Not portable - each microprocessor requires a different set of instructions

Question 38

Assembly code

Answer 38

One line of assembly code is one instruction Easier to understand than binary, as the mnemonics are similar to English.

Question 39

Secondary storage

Answer 39

**Stores data for long periods of time. ** * Easy portability * Faster read speeds * Greater durability

Question 40

Magnetic

Answer 40

** Large moving parts** * Series of polarised dots * Large capacity * Inexpensive * Lifespan until dots aren't polarised and cannot be read

Question 41

Optical

Answer 41

**Uses lasers to heat/burn pits and lands into a reflective surface that represents 1s and 0s -> binary code** * Moving parts * Small capacity * Cheap * Lifespan until information cannot be read

Question 42

Solid state

Answer 42

- If a row of transistors are charged, this represents a 1 - If a row of transistors is uncharged, this represents a 0 - Arranged in a gird - At row/column intersections, two transistors create a cell (control gate and floating gate) - Applying voltage to the control gate transistors causes electrons to flow onto the floating gate - Creates a net positive charge that interrupts current flow