Q. Show the fundamental process of instruction execution?
The fundamental process of instruction execution is:
1. Instruction is fetched from memory to CPU registers (called instruction fetch) under the control unit.
2. It is decoded by CU (control unit) and converted in a set of lower level control signals that cause the functions specified by that particular instruction to be executed.
3. After the completion of execution of current instruction next instruction fetched is the subsequent instruction in sequence.
This process is repeated for each instruction besides for program control instructions such as branch, jump or exception instructions. In this case next instruction to be fetched from memory is taken from part of memory specified by instruction rather than being next instruction in sequence.