State transition diagram

State transition diagram

State machine is composed of state register and combinational logic circuit , According to the control signal, the state can be transferred according to the preset state , It's to coordinate the relevant signal action , A control center that performs a specific operation . The finite state machine is abbreviated as FSM(Finite State Machine), Mainly divided into 2 Major categories :
first kind , If the output is only related to the state and not to the input , Is called Moore State machine
The second category , The output is not only related to the state, but also to the input , Is called Mealy State machine
State machine is composed of state register and combinational logic circuit , According to the control signal, the state can be transferred according to the preset state , It's to coordinate the relevant signal action , A control center that performs a specific operation . The state machine is divided into Moore (Moore) State machine and Millie (Mealy) State machine .
An extremely precise description of a state machine is : It is a directed graph , It consists of a group of nodes and a set of corresponding transfer functions . State machines respond to a series of events “ function ”. Every event belongs to “ current ” The control range of node's transfer function , Where the scope of the function is a subset of the nodes . Function return “ next ”( Maybe the same one ) node . At least one of these nodes must be a final state . When the final state is reached , State machine stop .
Contains a set of state sets (states), A starting state (start state), A set of input symbols (alphabet), A conversion function that maps input symbols and the current state to the next state (transition function) Calculation model of . When inputting a string of symbols , The model then enters the initial state . It's going to change to a new state , Dependent on conversion function . In a finite state machine , There will be many variables , for example , state The machine has a lot of movement (actions) transformation (Mealy machine ) Or state ( Moore machine ) Associated actions , Multiple initial states , Conversion based on no input symbol , Or specify the symbol and status ( Not necessarily Limited state ) Multiple transformations for , Assign to receive state ( Recognizer ) One or more states of , wait .

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