Made with

Finite State Machine

A finite-state machine can be known as “FSM, “finite-state automaton” (or “FSA”), “finite automaton” or a “state machine”. It is simply a mathematical model of computation, being an abstract machine in exactly one of a finite number of so called “states” at any time. The finite-state machine can change from one state to another. It is usually done in response to some external inputs. The so called “transition” is simply the change from one state to another. Any “FSM” can be defined by a list of its states as well as by its initial state and the conditions for each of the transitions.

The behaviour of each of the state machines can be observed in many devices. In modern society it can perform a predetermined sequence of actions, which depends on a sequence of events they are presented with. As an example, the vending machines can be mentioned. They simply dispense the products when the proper combination of coins is deposited. Another example can be elevators, whose sequence of stops is usually determined by the floors requested by its riders. The traffic lights are also a good example for the state machine as they change sequence when the cars are waiting on the road. The well-known combination locks are also the finite state machines, requiring the input of combination numbers, which all have to be input in the proper, definite order.

The finite state machines are studied in the more general field of “automata theory” knowing to be having less computational power to compare it to some other models of computation (for example, the “Turing machine”). The so called “computational power distinction” means there are some computational tasks which a “Turing machine” can do but a “FSM” cannot. The reason for this is because a finite state machine's memory is limited by the number of the states it already has.

A term “state” is a description of the status of a system, waiting for executing a so called “transition”, known to be a set of actions executed once a condition is fulfilled. Sometimes it can also be executed when an event is received. As an example: while using some audio system for listening to the radio, the receiving of the "next" stimulus results in moving to the next station. In this mentioned case the system is known to be in the so called "radio" state. Once the system is in the so called "CD" state, then the "next" stimulus ends in moving to the very next track. The identical stimuli trigger different the actions, which depends on the state taking place at the very this moment.

Sometimes, in some of the representations of the finite-state machines, the actions can be simply associated with a state. The so called “entry action” is known to be performing while entering the state and an “exit action” is performed while exiting the state.

The Unified Modelling Language has a notation for describing state machines, overcoming the limitations of traditional “finite state machines” during retaining their most main benefits as well as introducing the new concepts of orthogonal regions and hierarchically nested states. At the same time the notion of “actions” is being extended. To understand what exactly the term of “actions” means, we have to mention that once the so called “event instance” is dispatched, the state machine responds by these so called “performing actions”, which can be involved in changing a variable, invoking a function, generating some other event instance, changing to another state or performing I/O.

In the so called “extended state machines”, a transition can have a “guard”, meaning that the transition can "fire" only in case the guard evaluates to “TRUE”.

A state is known to be having many transitions in response to the same trigger, but there’s always a chance that this situation can create even more problems in the sequence of evaluation of the guards once the common trigger occurs. The “UML specification” intentionally does not stipulate any particular order, meaning that the guard expressions should have no side effects left.

UML state machines are popular for having the characteristics of “Moore machines” as well as “Mealy” ones. They are known to be supporting actions, depending on the so called “triggering event” and “the state of the system” as in Mealy machines. They also support the “entry” and “exit” actions, associated with states, not transitions (as in Moore machines).

Thus, the finite state machines are significant in many different areas, being subdivided into acceptors, transducers, sequencers and classifiers. They are being widely used in such fields of business activities, as linguistics, computer science, electrical engineering, philosophy, mathematics, logic, biology, etc. They are a class of automata studied in so called “automata theory” as well as the “theory of computation”. Finite state machines are used in computer science for modelling of application behaviour, software engineering, designing of hardware digital systems, network protocols, compilers as well as the study of languages and computation.

Once you need to create a Finite State Machine (FSM) diagram, one of the best tools may be ConceptDraw DIAGRAM diagramming and drawing software extended with ConceptDraw STORE application, where all the pre-made solutions full of the examples and templates as well as stencil libraries are. You can always download ConceptDraw DIAGRAM software as well as ConceptDraw STORE application, find the “Specification and Description Language (SDL) Solution” from the last mentioned product of CS Odessa to be able to create any needed diagrams within the Description Language field of business activity, including the finite state machine’s ones, within only an hour or so having all the needed tools, such as design elements of SDL Connectors from the stencil library and the pre-made templates of the SDL Diagrams which can be always used as drafts for your own smart as well as professionally looking drawings.

Finite State Machine *

Example 1. Design Elements. Finite State Machine Diagram
for Apple OS X and Windows

To design the Finite State Machine Diagram from the beginning in new ConceptDraw document, use the predesigned connectors and SDL design elements offered in quantity of 71 objects by 2 libraries of Specification and Description Language (SDL) Solution. The predesigned vector objects give the possibility easily draw any FSM Diagrams you want.

Thanks to the Specification and Description Language (SDL) Solution we also have a variety of SDL and FSM diagrams samples in ConceptDraw STORE. Each of them can be opened in ConceptDraw DIAGRAM and used as is or changed according to your needs.

Specification and Description Language (SDL) Solution in ConceptDraw STORE

Example 2. Specification and Description Language (SDL) Solution in ConceptDraw STORE

The Finite State Machine diagram you see on this page was created in ConceptDraw DIAGRAM software using the objects from the libraries of Specification and Description Language (SDL) Solution. An experienced user spent 25 minutes creating this sample in ConceptDraw DIAGRAM

Use the Specification and Description Language (SDL) Solution for ConceptDraw DIAGRAM software to create your own professional looking SDL and FSM diagrams quick, easy and effective.

All source documents are vector graphic documents. They are available for reviewing, modifying, or converting to a variety of formats (PDF file, MS PowerPoint, MS Visio, and many other graphic formats) from the ConceptDraw STORE. The Specification and Description Language (SDL) Solution is available for all ConceptDraw DIAGRAM users.


What Is a Concept Map →

What is a Concept Map and what software is effective for its design? A concept map or conceptual diagram is a diagram that depicts suggested relationships between concepts. As for effective software - we suggest you to pay attention for the ConceptDraw DIAGRAM diagramming and vector drawing software. Extended with Concept Maps Solution from the "Diagrams" Area it is a real godsend for you.What Is a Concept Map *
Picture: What Is a Concept Map
Related Solution:

UML Diagram Types List →

Two types of diagrams are used in UML: Structure Diagrams and Behavior Diagrams. Behavior Diagrams represent the processes proceeding in a modeled environment. Structure Diagrams represent the elements that compose the system.UML Diagram Types List *
Picture: UML Diagram Types List
Related Solution:

Diagramming Software for Design UML Object Diagrams →

UML Object Diagram shows the structure of a modeled system at a specific time. ConceptDraw Rapid UML solution delivers libraries contain pre-designed objects fit UML notation, and ready to draw professional UML Object Diagram.Diagramming Software for Design <br>UML Object Diagrams *
Picture: Diagramming Software for Design UML Object Diagrams
Related Solution:

Entity Relationship Diagram Software Engineering →

While designing a conceptual data model, you should use appropriate software. For instance, ConceptDraw DIAGRAM is a user-friendly ER diagram tool that has a lot of samples and templates to facilitate your work. A clear entity-relationship diagram helps to define the relations between system’s components. Software engineering is the section of a computer science engaged to design, realization, and support of complex software products. An ERD is a data modeling method that is widely applied in the software engineering practice. Commonly it is used for developing a structure of a a relational database. An entity relationship diagram is helpful for structuring and organizing databases that can be modeled using a relational structure. An entity relationship diagram is designed to depicts the interrelationships within the sets of entities which are accumulated in the database. Each entity represents a particular component of a data. Thus, ER diagrams depicts the logical structure of databases. ConceptDraw ER Diagrams solution provides software engineers with the professional tool for making entity-relationship diagrams.Entity Relationship Diagram Software Engineering *
Picture: Entity Relationship Diagram Software Engineering
Related Solution:

Interior Design. Machines and Equipment — Design Elements →

Any factory needs a clear scheme of all the equipment used in the manufacture processes. So, if you want to place all your machines and equipment on one diagram, you need a good diagramming tool for that. For instance, you can find all the design elements you might need, such as lathes, milling machines or saws on ConceptDraw DIAGRAM Solution Park in Plant Layout Plans solution in appropriate libraries. This drawing represents the Machines and Equipment library delivered by ConceptDraw Plant Layout Plans solution. This vector library is supplied along with other libraries related to industrial architecture planning and interior design. Just planning the proper facilities in a proper right place, allows to manufacture a product in the most effective and economic way. Objects containing in these libraries will be helpful for architects and engineers dealing with industrial buildings design. They are intended to use for designing layouts of plants, warehouses, manufacturing workshop etc.Machines and Equipment — Design Elements
Picture: Interior Design. Machines and Equipment — Design Elements
Related Solution:

Local area network (LAN). Computer and Network Examples →

Computer networks nowadays are spread all across the world. The large number of parameters, such as geographic scale or communication protocols, can divide networks. One of the most common types of networks is called local area network (LAN). It convenient to represent network examples by means of diagrams. This local area network (LAN) diagram provides an easy way to see the way the devices in a local network are interacted. The diagram uses a library containing specific symbols to represent network equipment , media and the end-user devices such as computers (PC, mac, laptop) , network printer, hubs, server and finally a modem. There are two types of network topologies: physical and logical. The current diagram represents precisely a physical type of LAN topology because it refers to the physical layout of a local network equipment.Local area network (LAN) diagram
Picture: Local area network (LAN). Computer and Network Examples
Related Solution:

Home area networks (HAN). Computer and Network Examples →

A Home Area Networks (HAN) is a type of local area network that is used in an individual home. The home computers can be connected together by twisted pair or by a wireless network. HAN facilitates the communication and interoperability among digital devices at the home, allows to easier access to the entertainments and increase the productivity, organize the home security. This example was created in ConceptDraw DIAGRAM using the Computer and Networks Area of ConceptDraw Solution Park and shows the home network diagram.Home area networks (HAN). <br>Computer and Network Examples *
Picture: Home area networks (HAN). Computer and Network Examples
Related Solution:

Sentence Diagrammer →

Sentence a grammatical unit of several words, and provides a narrative, question, comment, etc. It begins with a capital letter and ends with proper punctuation. Sentence diagramming allows you to visually present the sentence part function, which helps you build right sentences. Language Learning solution offers the Sentence Diagrams Library with set of vector stencils for drawing various Sentence Diagrams, for visualizing grammatical structures that will assist you in language learning and construction of grammatically correct sentences. ConceptDraw DIAGRAM diagramming software extended with Language Learning solution from the Science and Education area provides the powerful sentence diagraming tools.Sentence Diagrammer *
Picture: Sentence Diagrammer
Related Solution:

Living Room. Piano in plan →

Living room is the place where all family comes together, where receive guests. The interior of the living room complements the piano which helps to create a warm atmosphere. The piano is not just a musical instrument, in the room interior it becomes the most noticeable detail. The piano always organically entered in any interior. Best Interior Design Software for Mac OS&Windows ConceptDraw DIAGRAM allows you design the interior of your dreams quick and easy.Living Room. Piano in plan *
Picture: Living Room. Piano in plan
Related Solution: