Chapter 17: Hardware

Question 1

What does the Arithmetic Logic Unit (ALU) do?

Answer 1

Performs calculations and logical decisions within the CPU.

Question 2

What is the role of the Control Unit (CU)?

Answer 2

Sends signals to other parts of the computer system to control the movement of data around the CPU.

Question 3

What is Cache in a computer system?

Answer 3

A small amount of high-speed memory built within or very close to the processor. It temporarily stores & provides fast access to frequently used instructions & data, speeding up processing

(Primary memory & volatile)

Question 4

What is the function of the Clock in a CPU?

Answer 4

The electronic unit that synchronizes related components by generating pulses at a constant rate.

Question 5

What is a Bus in computer architecture?

Answer 5

A collection of wires for transmitting data and instructions between components.

Question 6

What is the Address Bus?

Answer 6

A unidirectional bus that carries addresses which data needs to be written to or read from.

Question 7

What is the Data Bus?

Answer 7

A bidirectional bus that carries actual data or instructions.

Question 8

What does the Control Bus do?

Answer 8

A bidirectional bus that carries commands and signals that control and coordinate all the activities within the computer and tell components whether to read or write the data and when to do so.

Question 9

What are Registers in a CPU?

Answer 9

Tiny, fast pieces of onboard memory inside the CPU each with a very specific purpose.

Question 10

What is the purpose of the Accumulator?

Answer 10

Holds results of calculations performed by the ALU

Question 11

What does the Program Counter do?

Answer 11

Holds the memory address of the next instruction to be fetched.

Question 12

What is the Current Instruction Register (CIR)?

Answer 12

Holds the instruction currently being executed.

Question 13

What is a CPU?

Answer 13

The central processing unit is responsible for handling/executing all the instructions received from the computer’s software and hardware.
It is made of transistors acting as on/off switches, controlled by electric signals.

Question 14

What is a Microprocessor?

Answer 14

An integrated circuit that contains a CPU.

Question 15

What factors affect CPU performance?

Answer 15

1. Number of cores: The more cores a CPU has, the greater the number of instructions it can process in a given space of time.
2. Cache size: The larger the cache, the better the CPU performance.
3. Clock speed: The faster the clock speed, the faster the rate of processing.

Question 16

What is Clock Speed?

Answer 16

Measures the number of instructions/cycles the CPU executes each second. Clock speed is measured in Hertz (Hz). The faster the clock speed, the faster the rate of processing

Question 17

What is the FDE Cycle?

Answer 17

A sequence of steps (Fetch, Decode, Execute) carried out repeatedly by the CPU.

Question 18

What happens during the Fetch step?

• CU
• Control (request to…)
• Data bus
• CIR

Answer 18

The CU places the memory address of the next instruction on the address bus, sends a signal to the control bus to request to read from memory, and the instruction/data in memory is copied onto the data bus which is then copied into the CIR by the CPU.

Question 19

What occurs during the Decode step?

Answer 19

The CU analyzes the contents of registers and sends signals to other CPU parts telling them what to do. It decodes the instruction into an opcode & an operand.

Question 20

What happens during the Execute step?

Answer 20

The instruction is completed by the CPU.

Question 21

What are System Buses?

Answer 21

A collection of wires for transmitting data & instructions between components.

Question 22

What is Bus Size?

Answer 22

The size of a bus in a computer determines how much data can be transferred at once. The wider the bus, the more data can be transferred, making the computer faster.

Wider buses can be more expensive.

Question 23

What is Memory in a computer?

Answer 23

The component of the computer that stores data & instructions.

Question 24

What is ROM?

Answer 24

Primary non-volatile storage that stores permanent data & instructions, can only be read from, cannot be written to, stores BIOS, and loads the operating system from secondary storage onto RAM when the computer is turned on.

Question 25

What is RAM?

Answer 25

Primary storage that is used to temporarily store data, programs & instructions currently in use. It is volatile and has faster read/write speeds than secondary storage. It can be read from & written to.

Question 26

Components of CPU

Answer 26

• Registers, Clock, ALU, CU

Question 27

Functions of OS

Answer 27

• It manages files by allowing them to be manipulated
• Process management by sharing processor time
• Manages memory by assigning blocks of memory to running programs as required
• Manages hardware to receive data from input devices & to send processed data to output devices