Systems Architecture [1.7]

Question 1

What is a General Purpose Computer?

Answer 1

A Computer designed to be able to carry out a wide range of instructions.

Question 2

What is an application?

Answer 2

A software program that allows a user to perform a specific task.

Question 3

What is hardware?

Answer 3

The physical parts of a computer system, eg a graphics card, hard disk drive or CD drive.

Question 4

What is software?

Answer 4

The programs (series of instructions) that run on a computer.

Question 5

What is Secondary Storage?

Answer 5

Non-volatile memory external to the computer and used for long term storage of programs and data.

Question 6

What is secondary storage held in while being processed?

Answer 6

Primary Memory.

Question 7

What is an input device?

Answer 7

A device used to input data or information into a computer, e.g a keyboard, mouse, scanner or microphone.

Question 8

What does the CPU do with instructions?

Answer 8

Sends it to an output or transfers it to secondary storage.

Question 9

What is the purpose of the CPU?

Answer 9

The CPU is the most important hardware component in a computer. It has two main functions:

Process data and instructions

Control rest of computer system

Question 10

What is the frequency of the clock pulses known as?

Answer 10

Clock Speed - Measured in hertz

Question 11

What is a bus?

Answer 11

High speed internal connection.

Question 12

What are buses used for?

Answer 12

Used to send control signals and data between processor and other components.

Question 13

What are the 3 types of buses called?

Answer 13

Address Bus - Carries memory addresses from the processor to other components such as primary memory and input/output devices

Data Bus - Carries actual data between processor and other components

Control Bus - Carries control signals from the processor to the other components. The control bus also carries the clock’s pulses.

Question 14

What is Von Neumann architecture?

Answer 14

A description of the processing architecture that all CPU’s use.

Question 15

What are the key elements of Von Neumann architecture?

Answer 15

Data and Instructions are both stored as binary digits.

Data and instructions are both sotred in primary memory.

Instructions are fetched from memory one at a time and in order.

Processor decodes and executes on instruction before cycling around to fetch the next instruction.

Question 16

What are the steps of the fetch, decode, execute cycle?

Answer 16

The memory address held in the program counter is copied into the MAR.
The address in the program counter is then incremented (increased) by one. The program counter now holds the address of the next instruction to be fetched.
The processor sends a signal along the address bus to the memory address held in the MAR.
The instruction/data held in that memory address is sent along the data bus to the MDR.
The instruction/data held in the MDR is copied into the CIR.
The instruction/data held in the CIR is decoded and then executed. Results of processing are stored in the ACC.
The cycle then returns to step one.