1.1 systems architecture Flashcards
what actions occur at each stage of the fetch-execute cycle
fetch – gets the next program command from the computer’s memory.
Decode – finds out what the program is telling the computer to do.
Execute – carries out the requested action.
Store – saves the results to a Register or Memory.
what is the role of the ALU in the fetch-execute cycle
For example, for an arithmetic instruction (such as adding two numbers together) any required data is fetched from the main memory, then the calculation is executed by the ALU
what is the role of CU and control during the fetch decode execute cycle
executes instructions and controls the flow of data in the CPU.
what is the role of the cache in the fetch-execute cycle
As part of the Fetch stage of the Fetch - Decode - Execute cycle, the CPU automatically checks in cache for the instructions before going to RAM for them.
what is the purpose of MAR and what does it store
it is a register that tracks the ram address of the instruction that is to be fetched
what is the purpose of mdr
the mdr stores the instruction that has been transferred from ram to the cpu
what is the purpose of the program counter and what does it store
a register that tracks the ram address of the next instruction to be fetched
what is the purpose of the accumulator
the accumulator stores the result of mathematical or logical calculations
whats the difference between storing data and an address
what is cache memory
cache memory is temporary storage for frequently accessed data.
describe 2 ways that more cache memory means performance will be higher
cache memory is closer to cpu than ram meaning it can provide data and instructions to cpu at a faster rate.
a computer with more cache memory should have a higher performance because repeatedly used instructions can be stored and accessed faster
explain why most computers only have a small amount of cache
it is costly so most computers only have a little
what is clock speed and what is it measured in
clock speed is a measure of how quickly a cpu can process instructions. it is measured in gigahertz
how does a higher clock speed improve performance
the faster the clock speed, the faster the computer can perform the fetch-execute cycle resulting in better performance because more instructions can be processed each second
what is a core
a core is a complete set of cpu components (cu,alu,registers). each core is able to perform its own fetch-execute cycle
