computer parts and software Flashcards
What is optical storage
Data is written onto the disc by a laser and is read from the disc by another laser
CD, DVD and Blu-ray discs are forms of optical storage
Advantage and disadvantage of optical storage
The discs are cheap but easily scratched
Operating Software definition
platform that gives the user an interface to the hardware
application software definition
application or ‘app’ - is not essential for the basic function of the computer
Arithmetic logic unit
Performs operations such as addition and subtraction, logical tests and comparisons
Control unit
Sends control signals to other parts of the CPU.
Clock
Uses a quartz crystal to synchronize the activities of the CPU
Bus
The wires that carry the data
from the CPU to the ALU
Fetch execute cycle
1 The processor checks the program counter to see which instruction to run next.
2 The program counter gives an address value in the memory of where the next instruction is.
3 The processor fetches the instruction value from this memory location.
4 Once the instruction has been fetched, it needs to be decoded and executed. For example, this could involve
taking one value, putting it into the ALU, then taking a different value from a register and adding the two together.
5 Once this is complete, the processor goes back to the program counter to find the next instruction.
6 This cycle is repeated until the program ends.
https://bam.files.bbci.co.uk/bam/live/content/zx46yrd/large
Motherboard-
Provides the connection between the PC components
Processor
Fetch, Decodes, Executes Instructions
RAM
Stores data, instructions, that are currently in use
PSU
supplies power to components
NIC
network interface card- allows you to connect to a network
hard drive
retains storage after PC turns off
