• The purpose of the CPU

• The fetch-execute cycle

• Common CPU components and their function:

  • ALU (Arithmetic Logic Unit)

  • CU (Control Unit)

  • Cache

  • Registers

• Von Neumann architecture:

  • MAR (Memory Address Register)

  • MDR (Memory Data Register)

  • Program Counter

  • Accumulator

• How common characteristics of CPUs affect their performance:

  • Clock speed

  • Cache size

  • Number of Cores

• The purpose and characteristics of embedded systems

• Examples of embedded systems

• The need for primary storage

• The difference between RAM and ROM

• The purpose of ROM in a computer system

• The purpose of RAM in a computer system

• Virtual memory

• The need for secondary storage

• Common types of storage:

  • Optical

  • Magnetic

  • Solid state

• Suitable storage devices and storage media for a given application

• The advantages and disadvantages of different storage devices and storage media relating to these characteristics:

  • Capacity

  • Speed

  • Portability

  • Durability

  • Reliability

  • Cost

• The units of data storage:

  • Bit

  • Nibble (4 bits)

  • Byte (8 bits)

  • Kilobyte (1000 bytes or 1 KB)

  • Megabyte (1,000 KB)

  • Gigabyte (1,000 MB)

  • Terabyte (1,000 GB)

  • Petabyte (1,000 TB)

• How data needs to be converted into a binary format to be processed by a computer.

• Data capacity and calculation of data capacity requirements

Numbers

• How to convert positive denary whole numbers to binary numbers (up to and including 8 bits) and vice versa

• How to add two binary integers together (up to and including 8 bits) and explain overflow errors which may occur

• How to convert positive denary whole numbers into 2-digit hexadecimal numbers and vice versa

• How to convert from binary to hexadecimal equivalents and vice versa

• Binary shifts

Characters

• The use of binary codes to represent characters

• The term ‘character-set’

• The relationship between the number of bits per character in a character set, and the number of characters which can be represented, e.g.:

  • ASCII

  • Unicode

Images

• How an image is represented as a series of pixels, represented in binary

• Metadata

• The effect of colour depth and resolution on:

  • The quality of the image

  • The size of an image file

Sound

• How sound can be sampled and stored in digital form

• The effect of sample rate, duration and bit depth on:

  • The playback quality

  • The size of a sound file

• • The need for compression

  • Types of compression:

    • Lossy

    • Lossless

• Types of networks:

  • LAN (Local Area Network)

  • WAN (Wide Area Network)

• Factors that affect the performance of networks

• The different roles of computers in a client-server and a peer-to-peer network

• The hardware needed to connect stand-alone computers into a Local Area Network:

  • Wireless access points

  • Routers

  • Switches

  • NIC (Network Interface Controller/Card)

  • Transmission media

• The Internet as a worldwide collection of computer networks:

  • DNS (Domain Name Server)

  • Hosting

  • The Cloud

  • Webservers and Clients

• Star and Mesh network topologies

• Modes of connection:

  • Wired

    • Ethernet

  • Wireless

    • Wi-Fi

    • Bluetooth

• Encryption

• IP addressing and MAC addressing

• Standards

• Common protocols including:

  • TCP/IP (Transmission Control Protocol/Internet Protocol)

  • HTTP (Hyper Text Transfer Protocol)

  • HTTPS (Hyper Text Transfer Protocol Secure)

  • FTP (File Transfer Protocol)

  • POP (Post Office Protocol)

  • IMAP (Internet Message Access Protocol)

  • SMTP (Simple Mail Transfer Protocol)

• The concept of layers