computer architecture

Question 1

CPU

Answer 1

central processing unit
- interprets and executes programming instructions

Question 2

ALU

Answer 2

Arithmetic Logic Unit
- does all arithmetic and logical operations
- math
- core
- dual core - two simultaneous operations

Question 3

CU

Answer 3

control unit
- loading and decoding of instructions
- directs data flow and operation of the ALU

Question 4

CPU registors

Answer 4

• small circuits in which intermmediate values from the calculations from ALU are stored
• stores instructions from CPU
• MDR, MAR, Accumulator, PC

Question 5

Accumulator

Answer 5

results of the currently running instructions

Question 6

PC

Answer 6

program counter
- address of the next needed instruction

Question 7

MAR

Answer 7

memory address register
- address bus
- stores memory address
- contains RAM address of the next instruction

Question 8

MDR

Answer 8

memory data register
- data bus
- contains data that will be written to RAM or was read from RAM

Question 9

RAM

Answer 9

random access memory
- volatile - loses data after power’s lost
- contains data and instructions that computer has loaded ever since booting up

Question 10

ROM

Answer 10

read only memory
- non volatile
- has the basic input output system that lets the computer know how to find the operating system to boot it after power’s restored
- data couldnt be changed before but now can be through flash upgrades

Question 11

diff b/w RAM and ROM

Answer 11

RAM : volatile, gigabytes, has all the data and instructions since computer was booted up
ROM : non-volatile, kilobytes, basic input output system

Question 12

CIR

Answer 12

current instruction register

Question 13

BUS

Answer 13

wires that connect two components of a computer system

Question 14

types of busses

Answer 14

• control bus
• data bus
• address bus

Question 15

cache

Answer 15

fastest way to access data
ONLY from FREQUENTLY accessed sites
CPU only goes to cache instead of RAM

Question 16

3 levels of cache

Answer 16

L1 - Smallest, Fastest, in CPU
L2 - Medium, Fast, outside processor chip
L3 - Largest, Slowest, in motherboard

Question 17

machine instruction cycle

Answer 17

fetch - decode - execute - store

Question 18

explain cycle

Answer 18

instruction fetched from main memory, instructions decoded into commands in CU, commands executed in ALU, results stored in main memory

Question 19

detailed cycle

Answer 19

address stored in PC, goes to MAR, back to register.
from there, data for that address stored in MDR, goes to CIR.
Control bus takes it to CU, address bus takes to MAR with instruction which reads data for that instruction
Data stored in mDR, goes to accumulator,
Next adress, cycle repeats, new data gone to accumulator
both data go to ALU to be calculated
Accumulator has the new value
cycle repeats

Question 19

detailed cycle

Answer 19

PC (address) - MAR (address) - address - MDR (instruction) - CIR (instruction) - CU (instruction) - MAR (instruction) - instruction - MDR (data) - ACC (data) - ALU - MDR

Question 20

persistent memory and its need

Answer 20

maintains data after power outage,
- keeps files for later use
- prevent data loss

Question 21

Solid State Drive (SSD)

Answer 21

flash based memory thats faster than a hard disk
- USB
- hard drives
- sim card

Question 22

OPERATING SYSTEM

Answer 22

OS
software that supports the computer’s basic functions

Question 23

GUI

Answer 23

graphic user interface
- windows, menu, icons to manage user’s interaction with system

Question 24

CLI

Answer 24

Command line interface
text based user interface to run programs, manage files and interact with the computer

Question 25

memory management

Answer 25

keeping track of storage devices
- which application has access to which area of memory
- each location in memory can be read, modified and written to by OS

Question 26

peripheral management

Answer 26

• keyboard, mouse, monitor, and printers controlled through device driver in peripheral management

Question 27

multitasking

Answer 27

multiple tasks processed in single resource

Question 28

multiprogramming

Answer 28

multiple programs run together

Question 29

security

Answer 29

prevents unauthorised access
- user name, passcodes

Question 30

application software

Answer 30

computer software package that performs a specific task directly
- spreadsheets, CAD (computer aided design), Web browser

Question 31

features of application software

Answer 31

toolbars, menus, dialogue boxes, GUI