4 Events that occur in the Fetch-Execute cycle?Watch
- My teacher did a really poor job of explaining the CPU registers, I have a vague idea of what they are and do but not how they link in with the fetch execute cycle.
To my understanding the CPU fetches an instruction from the memory, the CPU decodes it then executes it. For a 4th event can I say the ALU then decides what operation to apply to the instruction? Or that the address is stored in the MAR until it's been executed. I'm studying at GCSE level and any help is appreciated. Thanks
MAR ← [PC] (contents of the Program Counter copied to the Memory Address Register)
MDR ← [Memory] addressed (contents of addressed memory is copied to the memory data register/memory buffer register)
PC ← [PC] + 1 (incrementing the PC by 1.)
CIR ← [MDR] (if contents of MDR is an instruction, it is copied to the Current Instruction Register)
[CIR] decoded and executed