introduction of elevator project

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Introduction
The elevator control system is basically finite state machine (FSM). FSM is a digital sequential circuit that consists on different defined states that are controlled by inputs. Finite state machines categorized in two types Asynchronous and Synchronous FSMs. Asynchronous FSMs also called Moore machines in which output depends only on the current state while synchronous FSMs also called Mealy machine in which outputs is generated by using current state and the input variables. The given elevator control system is based on Mealy machine.
Moore FSM
Output is a Function of Present State Only. Outputs are independent of the inputs, i.e. outputs are effectively produced from within the state of the state machine.
 
Figure 1: how occur the process of Moore FSM
Mealy FSM
Output is a Function of a Present State and Inputs. Outputs can be determined by the present state alone, or by the present state and the present inputs, i.e. outputs are produced as the machine makes a transition from one state to another.
Figure 2: how occur the process of Mealy FSM