end of year revision Flashcards
What does the fetch decode execute cycle do?
- An instruction is fetched from memory
- The instruction is then decoded
- The decoded instruction is then executed so that the CPU performs continuously
- Process is repeated
when does fetch decode execute cycle happen
from boot up until the computer shuts down in order to process instruction
MAR
holds the address of the current instruction that is to be fetched from memory
MDR
holds the contents found at the address held in the MAR
PC
holds the memory address of the next instruction to be fetched from primary storage.
ACC
An accumulator is a type of register for short-term, intermediate storage of arithmetic and logic data in a computer’s CPU
CU
control unit controls the flow of data in a system
Register
One of a small set of data holding places that are part of the computer processor, It is quickly accessible location for the cpu.
Cache
a small and fast memory storage in a computer’s central processing unit (CPU), used to temporarily store frequently accessed data to improve overall system performance.
Clock speed
frequency of the number of fetch decode execute cycle per minute
Difference between storing data and an address
Data is the term used to describe information, and address is the term used to describe the location of an item of information.
Why does having higher clock speed increase the speed of the computer
More fetch decode execute cycles will be completed per minute.
Examples of volatile and non-volatile memory storage:
Volatile: Cache Memory, RAM
Non-Volatile: HDD, SSD, tape drives
why does computer have primary storage?
Primary storage provides fast access to the CPU. That allows active programs to deliver optimal performance to the end-user.
How are characters represented in binary form?
The ASCII code takes each character on the keyboard and assigns it a binary number
Define a character set
All of the characters that a computer can use
define metadata:
a set of data that describes and gives information about other data.
why is secondary storage needed
to keep programs and data indefinitely. It is non-volatile and long term storage
what are bitmaps
A bitmap is a file format used to store digital images.
How are images represented in binary
Every pixel in an image is made up of binary number. So the whole picture is made up of binary numbers.
what is sample rate measured in
Hertz (Hz)
Cauculate sound file size
sample rate x duration x bit depth
cauculate image file size
colour depth x image height x image width
Cauculate text file size
bits per character x number of character
What is defragmentation
the process of rearranging the data on a storage medium, such as a hard disk drive, for efficient storage and access.
Definition of a protocol
an agreed way of how to communicate over a network
Two uses of routers
connect multiple devices to a network and to enable communication between different networks
Definition of Lan
Lan covers a small geographical area and has it’s own infrastructure
Definition of Wan
Wan covers a large geographical area and uses shared infrastructure
what is POP
Post Office Protocol (POP) allows emails to be downloaded and /or deleted from a mail server and viewed offline by an email
what is IMAP
Internet Message Access Protocol (IMAP) downloads the email and makes a copy of the email and leaves it in the server
What is SMTP
Simple Mail Transfer Protocol is used for sending the email
why doesn’t doubling the cores double the speed of computer
CPU cores have to communicate with each other through channels and this uses up some of the extra speed.
Definition of embedded system
a small computer that forms part of a large system
What are utility softwares
Dedicated programs used for the maintenance of a computer system
