section 1 components of a computer system Flashcards
what are embedded systems
computers built into other devices often used a control system
pros of embedded systems
easier to design , cheaper and efficient
what is the power supply
supplies power to motherboard
what is the cooling fan
extracts hot air
what is the CPU heat sink and cooling fan
keeps CPU at steady temp
what is the CPU
does all the processing
what is the motherboard
main circuit board in computer
what is the optical drive for
for read/writing
what is the hard disk drive
internal secondary storage
what is the graphics card
controls the graphics
what are the two types of computer system
general purpose
dedicated systems
what is the purpose of a computer
take data, process it, then output it.
complete tasks more efficiently
what is hardware
physical stuff that makes up your computer
what is software
programs that the computer system runs
what is the CPU
brain of the computer
processes all the data and instructions
what does the CPU depend on for processing power
clock speed
number of cores
cache size
what is the control unit and what does it do
executes program instructions by following the fetch-decode-execute cycle
controls the flow of data
what is the Arithmetic logic unit
does all the calculation and performs logic operations
what is the cache
fast memory in the CPU
stores regularly used data so that the CPU can access it quickly
caches have low capacity and are expensive
what are buses
collections of wires that are used to transmit data between components of the CPU
what is the clock
sends out a signal that continually cycles between 1 and 0
the number of clock cycles per second is called the clock speed
what does the ALU do
gets data from the CPU and register performs an operation and outputs it back
what are registers and what does the registers do
used to store intermediate results of calculations
hold data, instructions and memory addresses that are about to be used by the CPU
how does the fetch decode execute cycle work
1) The program counter gets the next instruction
2) processor then collects the address data from the MAR
3) The processor then fetches the data from memory the via the data bus
4) stored in MAR via the address bus
4) The instruction is then decoded by the ALU that does all the calculations
5) the processor then goes back to the program counter to collect the next instruction
what are the two types of register
memory data register
memory address register
what does RAM stand for
Random access memory
what is RAM and what does it do
main memory that is volatile
operating system is copied from secondary storage to RAM
Data stays in RAM until files are closed
what is ROM and what does it do
Read only memory that is non volatile
contains the BIOS that tells the CPU what to check during start up
how much ROM and RAM do embedded systems need
more ROM because they don’t write much
ROM and RAM stored on the same chip as the CPU
how much ROM and RAM do non-embedded systems need
Have more RAM because they need to write data to main memory
ROM and RAM stored on the motherboard
how does clock speed effect performance of the CPU
The number of instructions a single processor core can carry out per second
how does cores effect performance of the CPU
each core process data independently of the rest
the more cores the more instructions it can carry out at once
how does cache size effect performance of the CPU
a larger cache gives the CPU faster access to more data it needs to process
how does cache type effect performance of the CPU
Has levels of L1, L2, L3
Higher the level the more it can hold, but the slower it is
speed based on how far it is from the CPU
how does RAM effect performance of the CPU
too little RAM won’t keep all data loaded at once slowing system down
more RAM more application
if user has enough RAM increasing RAM will make no difference
what is primary storage
memory areas that the CPU can access directly
fastest read write and is mostly volatile
what is secondary storage
non volatile storage that isn’t directly accessible to the CPU
what are HDDs
traditional internal storage that is made up of magnetised metal disks
they are long lasting but get damaged
what is magnetic tape
reels of tape that are read/written sequentially by the tape drive
advantages of magnetic tape
high capacity
low cost
reading/writing is fast once it has found data
disadvantages of magnetic tape
slow at finding data
what are SSDs
storage devices with no moving parts used for internal storage
advantages of HDDs
cheaper
high capacity
longer readwrite life
advantages of SSDs
faster
shock-proof
silent
don’t need defragmenting
usb drive(what is it and advantages and disadvantages
solid state storage
slower than SSD
capacity is high for size
advantages of optical disks
cheap
portable
won’t be damaged by water
disadvantages of optical disks
low capacity
slow read/write
streaming and downloading is better
what is cloud storage
a service where files can be uploaded via the internet to a remote server
what is utility software
software used to maintain or configure a computer
What is defragentation
Files are stored on a hard disk in available spaces
eventually as files are moved and deleted gaps appear on the disk and the OS has to fill the gaps making the files slower as read/write has to move back and forth
Defragmentation puts the files back into one block and collects the free space together
what does disk health do
hard drives start to deteriorate causing corrupted data
and disk health scan the drive for problems and fix it
what does compression do
reduces the size of files so they take up less disk space
what does encryption do
scrambles data to stop third parties from accessing it
to access it you need a key
what does backup do
copy of a computer systems files and settings stored externally that can be restored in event of data lose
the back up software schedules regular backups
what do virus scanners do
inspect each file on your computer , looking for viruses
what does system clean up do
web browsers leave a lot of temporary files and cleanup gets rid of them
what are the main functions of the OS
communicate with input and output devices
provide a platform for applications to run on
controls memory management
organise the CPU
deal with file management and disk
manage system security
what are l/0 devices
(input/output)allow computers to take inputs and give outputs
how doe’s the OS communicate with the l/0 device
l/0 devices require a device drive and these act as translators for the signals between both the OS and device
when computer is booted up the OS will find the correct device drivers for the device it detects
device manufactures may release updates and these may be installed automatically
how the OS manages Applications
it provides a platform to run off
allows then to access hardware and other devices like RAM and storage
provides a user interface that applications are accessed through
how does the OS take charge of memory management
copies necessary parts of the application to memory, followed by additional parts when required
manages how much RAM a program has access to
when running multiple applications the OS stops interference with each other by allocating memory addresses
how does the OS take charge of memory management
copies necessary parts of the application to memory, followed by additional parts when required
manages how much RAM a program has access to
when running multiple applications the OS stops interference with each other by allocating memory addresses
how the OS tells the CPU what to process
use scheduling to determine the most efficient order using priority
the instruction with the highest priority goes to the CPU first
OS can interrupt if a more important instruction comes up
how the OS handles files
use file extensions to tell the computer what software is needed
deals with the movement, editing and deletion of data
how the OS handles disk management
splits the physical disk into storage sectors and keeps track of free space on the disk
maintains the hard disk with utility software
how the OS manages security
use user account control
can only access there personal data and not others
have anti theft measures such as passwords
what is open source software
software where the source code is made freely available
what examples are there for open source software
GIMP , firefox
advantages of open source software
free made for greater good software can be adapted collaborators are creative very reliable and secure
disadvantages of open source software
won't update regularly buggy security holes no warranties no customer support
what is proprietary software
software where only the compiled code is released
examples of proprietary
microsoft
adobe
advantages of proprietary software
comes with warranties, documentation, customer support
well tested and reliable
cheaper for companies than developing thier own custom built software
disadvantages of proprietary software
expensive
may not fit a users needs
may not maintain older software after warranties expire
what is the program counter
holds the address of the next instruction
what is the accumulator
where arithmetic are temoraliy stored
what is the MDR
holds the next instruction and then the data copied from the RAM
what is the MAR
holds the address of the current instruction and address of that data
