fetch-execute cycle

HELP

what is step 1

fetch information from the primary storage (memory)

what is step 1a

CPU → address bus → memory → data bus → memory data register

what is step 2

decode information into operation code and data addresses

what is step 2a

copy instruction code from memory data register into instruction register

what is step 2b

copy address of the data into address register

what is step 2c

use address register to copy data into storage register

what is step 2d

send operation code and data to ALU

what is step 3

execute the instruction on the data

what is step 3a

send result to accumulator (register), ready for next instruction

what is step 4

store the result in primary storage (memory)

what is step 4a

result → data bus → stored in memory