Mealy Machine and Moore Machine

According to the theory of computer science, the Mealy machine is a finite state machine. Its output variables are determined by its current state and current inputs. This is the total opposite of the Moore machine, where its output value is dependent only on the current state. Instead, a mealy machine works as a deterministic finite-state transducer. It works in every state and at every input. The Mealy machine originated from its inventor George Jon Mealyy, who represented the concept in a paper in 1955.

These Mealy machines provide a mathematical model for the machines. A Mealy machine is designed along with a given set of strings of letters that can process it into a ciphered string. The Mealy model can also be used to describe the Enigma. However, the state diagram would be too complex to provide a basic idea of designing the complex ciphering machines.

Moore/Mealy machines are DFA’s that also have output at any tick of the clock. Modern CPUs, computers, cell phones, digital clocks, and primary electronic devices/machines have finite state machine control.

Simple software systems can be represented using regular programming and modelled as Finite State Machines. The intersection between the two Finite state machines, where one can design in a straightforward manner concurrent systems which can exchange messages. For example, a traffic light is a system that consists of multiple subsystems, such as the different traffic lights that work with proper coordination.

About Moore Machine:

According to computer science theory, Moore’s machine is a finite state machine. Only its current state inputs determine its output variables. This is the absolute opposite of the Mealy machine. Like others, the finite state machines, the input typically influences the upcoming steps in Moore machines. Thus the information may indirectly influence subsequent outputs, but not the current or immediate output. The Moore machine is named after Edward Moore, who presented the concept in a 1956 paper.

Moore and Mealy machines are two types of finite-state machines. Either type can be the difference between Moore machines and Mealy machines. The output of a transition is determined by combining the current state and current input for a Moore machine. Each node (form) is labelled with an output value.

Every Moore machine is equal to the Mealy machine with the same states, transitions, and output function. This takes each state-input pair which yields where the equivalent output is.

However, not every Mealy machine can be converted to an equivalent Moore machine. Some can be converted only to an almost identical Moore machine, with outputs shifted in time. This is due to how state labels are paired with transition labels to form the input/output pairs if we consider a transition. The input causing the change moves to the edge. The output which corresponds to that input is the label of the state is the source state of the transition. So for every information, the outcome has been already fixed before the information has been received and depends solely on the current state. This is the original definition by E. Moore. It is a common mistake to use the label of a state as output for the transition

Differences Between Moore and Mealy Machine:- (On basis of different parameters)

Conclusions

Now that concludes the similarities and differences between the two machines, as both devices are equivalent since they can be converted to each other. However, a Mealy machine requires a few more states to implement a function. On the other hand, a Moore machine will have more states to implement the same function.