Hardware Flashcards
Expand CPU
Central Processing Unit
What is CPU often reffered to as?
Brain of the computer
Explain Fetch execute Cycle
Process programs and data by repeatedly fetching an instruction from memory and executing it
What are the three main components of CPU
Control Unit
Arithmetic and logic unit
Immediate access store
Explain Control Unit
manages the execution of instructions one at a time using fetch execute cycle
What are the three jobs of Control Unit
1) decide which instruction to carry out next and fetch it from memory
2) To decode the instruction
3) to execute the instruction
Explain ALU
This component carries out arithmetic calculations to be carries out(+ - * /)
Perform logical comparision
such a ‘And’ and ‘NOT
What is a Program counter?
The Program counter is the CPU register that stores the address( memory location reference) for the next instruction to be fetches
Explain the steps in Fetch Execute Cycle
1)The processor check 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 its memory location
4) Once the intruction has been fetches, it needs to be decoded and executed
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
What is Fetch-Execute cycle?
Fetching instruction from its memory and executes it
What is Program counter
CPU register that stored the address of the next instruction to be fetched
What is an Accumulator
When calculations take place on data, the results are initially stored on accumulator before transferred and stored in the main memory
What is an Instruction Register
stores the current instruction to be decoded and then execution
What are the factors that influence the speed of processing
(not in our mocks)
Clock Speed
Cache
Processor Core
Expand MDR
`Memory Data Register
Expand MAR
Memory Address Register
What is MDR
MDR temporarily stores data being fetched from or written memory
What is MAR
MAR Temporarily stores current instruction or data
3 Types of Internal memory
RAM
ROM
Cache
Expand RAM
Random Access Memory
Expand ROM
Read Only Memory
Explain RAM
Can be read from or written
Volatile
used to hold programs and data that are currently being used(operating System)
Explain ROM
Non Volatile
Can be read but not written
Used to store programs that are frequently required by the computer ( boot program)
Explain Cache
Temporarily stored frequently used instructions and data
Quicker to store cache memory as it has a smaller storage capacity compared to RAM
What does Volatile Mean?
Means if the computer is closed then reopened, the ROM would stay open
Explain Immediate Access Store
Stores all programs and data temporarily in use
