Hardware and Software

Question 1

Give examples of input hardware.

Answer 1

-eg. Keyboards, composite devices (capable of multiple things such as game controllers or light pen), and point devices (eg mouse)

Question 2

What is output hardware and give examples.

Answer 2

• transmitting data in a form humans can understand

- eg. Monitors, printers, haptic sensors, sound cards and speakers

Question 3

Give a list of all the places you can store data.

Answer 3

• Hard Disk Drives (HDDs)
  - Solid-state drives (SSDs)
  - Optical drives (CDs / BluRay / DVD)
  - Flash storage devices (USB storage disks)
  - Floppy disk drives (obsolete in today’s world)
• Network-attached storage devices (NAS)

Question 4

What is the main thing that the CPU handles

Answer 4

Processing

Question 5

Explain the CPU

Answer 5

• The purpose of a CPU is to process data and control other components within the computer system.
  - The CPU is located on a ‘motherboard’.
  - The three main parts of a CPU are the Control Unit, Registers and the Arithmetic Logic Unit (ALU).
  - The three main buses are Data bus, Address bus and the Control bus. These connect parts of the computer system.
  - The cache (in the CPU) is a very fast but small type of RAM.
  - The CPU runs at the speed of its clock.

Question 6

What is the ALU

Answer 6

• Stands for Arithmetic Logic Unit
• The Arithmetic Logic Unit (ALU) handles the data processing inside the CPU. It consists of two types of processing
• Arithmetic operation - it performs standard arithmetic operations such as addition, subtraction, multiplication etc
• Logic operation - it deals with logic and comparisons such as ‘is this value greater than that value’ the answer is always either ‘true’ or ‘false’.

Question 7

What is the CU

Answer 7

• Control Unit
• It controls the way data moves around the CPU (timing signals)
• It executes the instructions provided by the program (control signals)
• It controls and monitors the flow of data between the CPU and other components such as input devices, memory, graphics card etc (signals to memory/devices)

Question 8

What is a register?

Answer 8

• A ‘register’ is a type of memory inside the CPU.
• A register can hold a data value.
• Registers are used to hold temporary data while a software program is running. As the CPU processes the data, the software program will shift the data in and out of the registers.
• There are usually many registers available inside the CPU.
• Some registers in the CPU have a specific purpose and so they have their own name.
• not cache

Question 9

Whats a system clock?

Answer 9

• The clock is a tiny quartz crystal inside the CPU chip that ‘ticks’ at a steady speed.
• The CPU can only do something when the clock ticks. In-between each tick it does nothing. During each ‘tick’ the CPU can process a single instruction.
• However, the clock ticks extremely fast so you will not notice the delays in between each tick.
• A typical computer has a clock speed of around 3GHz. So the CPU can carry out three thousand million instructions per second at that speed.

Question 10

Whats a Program Counter?

Answer 10

• Memory is split up in to memory locations
• The program counter stores the address (location) of the instruction being processed at any point in time
• As each instruction is fetched, the program counter increments (increases) by 1
• This allows the computer system to indicate where the program is in its instruction sequence

Question 11

What are buses?

Answer 11

• Buses are communication systems inside a computer that transfers data between components
• A computer utilizes buses to send and receive binary data as encoded electrical signal

Question 12

Types of buses:

Answer 12

control, address, data

Question 13

Whats a control bus?

Answer 13

• The control bus is used by CPUs for communicating with other components and peripherals in a computer system
• This bus is responsible for managing information flow between components
• It indicates whether the operation is read or write
• The control bus also ensures that the operation is happening at the correct time

Question 14

Whats an address bus?

Answer 14

• The address bus specifies the the location of a physical memory address
• The location refers to the memory address that the processor will read data from or write data to
• This includes primary memory, secondary memory and other connected peripherals
• The width of an address bus is responsible for the amount of memory that can be addressed

Question 15

Whats a data bus?

Answer 15

• The data bus contains the actual data being sent around the computer system
• The data bus is responsible for connecting the CPU to other devices on the system
• Unlike the address bus, the data bus is capable of two way operations
• This means it supports both read and write operations
• The data bus is also responsible for transferring program instructions to the CPU