1. CPU components Flashcards
(25 cards)
Fetch phase
CPU fetches instructions from RAM and takes them to CPU
Decode phase
CPU decodes instructions and if all the parts of the instruction is there, execution can be carried out
Execute phase
Where data is processed, instructions are carried out on the data
Cache
Super fast and small pieces of memory that stores frequently used instructions, it is located next to CPU
ALU
Makes arithmetic calculations and logical decisions
Control Unit
Controls the functions of the computer system, synchronises FDE cycle
BUS types
Data, Address and Control
BUS
All separate buses for each type, gets carried from CPU to RAM
Types of Registers
Program counter, MAR, MDR & Accumulator
Program counter
Holds the address of the next instruction to be executed in memory
MAR
Holds memory address of the current instruction to be executed
MDR
Holds data fetched from memory to be executed
Accumulator
Holds results of calculations
Volatile
temporary data
Non-volatile
permanent data
Clock speed
Amount of FDE cycles that can be performed per second
CPU cores
Independent processing unit that is able to fetch, decode and execute instructions a small copy of CPU.
Clock speed measurement
Hertz (Hz)
Primary storage examples
Cache, RAM & ROM
Secondary storage examples
Hard disk, Flash drive
Characteristics of primary storage
Volatile (except ROM), More expensive and smaller, smaller capacity & faster as its closer to the CPU
Characteristics of secondary storage
Non-volatile, cheaper and larger, bigger capacity but slower as its far away (connects via cable)
Virtual memory
When RAM is full, CPU makes use of HDD to hold the currently running instructions
Multicores
Can do multiple FDE cycles to execute instructions faster, does multitasking
