Show how finite state machine model helps in designing a switching system and give a typical example.

Show how finite state machine model helps in designing a switching system and give a typical example.
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Switching system basically belongs to the class of finite state machines (FSM) which are asynchronous in nature and follows a sequential logic for their operation. They can be modeled by using a combinational part and a memory part as shown in Fig.. In FSM , the status of the output circuits not only depends upon the inputs but also upon the current state of the machine. Asynchronous sequential operation gives rise to many problems due to transient variations that may occur in the logic circuits and memory elements. Clocked synchronous operation shown in Fig. overcome such problems.

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