Machine Cycle

A machine cycle, also called a processor cycle or an instruction cycle, is the basic operation performed by a central processing unit (CPU). A CPU is the main logic unit of a computer.  An Arithmetic and Logic Unit (ALU) is a digital circuit that performs integer arithmetic and logical operations. The ALU is a fundamental building block of the central processing unit of a computer, and even the simplest microprocessors contain one for purposes such as maintaining timers. 

The steps performed by the computer processor for each machine language instruction received. The machine cycle is a 4 process cycle that includes reading and interpreting the machine language, executing the code and then storing that code.

       Four steps of Machine cycle

1. Fetch - Retrieve an instruction from the memory.
2. Decode - Translate the retrieved instruction into a series of computer commands.
3. Execute - Execute the computer commands.
4. Store - Write the results back in memory.