Fundamentals of Computer Systems

Question 1

What is Hardware?

Answer 1

The physical components of a computer system.

e.g. keyboard, mouse, mic

Question 2

What is Software?

Answer 2

The code or programs that run on the hardware.

e.g. word processor, Microsoft edge, photoshop, Visual Studio

Question 3

What is System Software (+ what are its 4 main types)?

Answer 3

System software aids in system running. any software that assists with the running or management of the computer system.

• OS
•.Utility
• Library
• Translators: Assembler, Compiler, Interpreter

Question 4

What is an Operating System?

Answer 4

Allows the user to control the computer with ease.

It provides a virtual machine, hiding the true complexity of the computer from the user.

As a result, we can use other computers with the knowledge from another due to the OS.

e.g Windows, Ios, Linux.

Handles: memory management, processor scheduling etc.

Question 5

What are Utility programs?

Answer 5

Used to complete housekeeping tasks in the computer system.

e.g. data backup, defragmenting hard drives (reorganising data on a hard drive to improve speed of access), data compression and encryption, antivirus etc.

Question 6

What are Library Programs?

Answer 6

Libraries contain useful functions that are frequently used by a program.

Programmers make use of libraries when developing a program to simplify the process.

Must he imported within their program.

Speedily make a program.

e.g. Netframework, Netcore, OpenSSL

Question 7

What are Translators?

Answer 7

Pieces of software which translate between different types of programming languages.

Microsoft Visual Studio (Compiler)
Python (Interpreter)
Fortran Assembly Program (FAP)

Question 8

The Fetch & Execute Cycle

Answer 8

Program Counter
Memory Address Register
Address Bus
Main Memory
Data Bus
Memory Data Register
Current Instruction Register
PC + 1
Decode
Opcode
Operand
Execute

Question 9

What does the PC (program counter) do?

Answer 9

holds address of the next instruction

Question 10

What does the MAR do?

Answer 10

holds the address you’re accessing in memory.

Question 11

What does the address bus do?

Answer 11

Transports memory addresses, specifying where data is to be sent to or retrieved from.

Question 12

What does Main Memory do?

Answer 12

Memory that can be directly accessed by the processor.

Allows system to run instructions.

e.g. RAM, ROM

Question 13

What does the Data Bus do?

Answer 13

Sends data and instructions to and from the different components of the computer system.

Question 14

What does the MDR do?

Answer 14

Holds the contents of a memory location that has been read from, or data that is to be stored

Question 15

What does the CIR do?

Answer 15

holds current instruction.

Question 16

What does PC + 1 do?

Answer 16

The program counter is incremented by 1 to access the address of the next instruction that needs to be executed.

Next instruction to be executed typically kept in the following memory location.

Question 17

What happens in the DECODE stage?

Answer 17

The control unit decodes the instruction in the CIR into OPCODE and OPERAND.

Question 18

What is Opcode?

Answer 18

code needed to perform the instruction.

Question 19

What is Operand?

Answer 19

Pieces of data that come with the instruction.

Question 20

What is meant by a register?

Answer 20

A small, fast memory location in the CPU.

Question 21

What is meant by addressable memory?

Answer 21

each memory location has an address.

Question 22

What is the STORED PROGRAM CONCEPT?

Answer 22

Machine code instructions stored in main memory are fetched and executed serially by a processor that performs arithmetic and logical operations.

Question 23

What does the control bus do?

Answer 23

carries control signals that regulate the operation of the computer system.

e.g. clock, interrupt, reset, stats, I/O write, I/O read, memory read, memory write, transfer request

Question 24

What is Von Neuman Architecture?

Answer 24

• data and instructions stored in main memory.
• instructions sent to processor along system bus.
• data sent to and from processor is sent along system bus.
• all input/output transported by system bus.

• fear of bottlenecking, cannot do simultaneously.

Question 25

What is Harvard Architecture?

Answer 25

Separate buses used for data and instruction, both of which address different parts of memory.

Used for embedded systems such as cars, washing machines etc.

Question 26

What is Direct Addressing?

Answer 26

A form of addressing an instruction such that the operand is the address of the required datum (singular of data)

Question 27

What is Immediate Addressing?

Answer 27

A form of addressing an instruction such that the operand is the require datum (singular of data)