Difference between Mealy machine and Moore machine

senseadmin
2 Min Read
Disclosure: This website may contain affiliate links, which means I may earn a commission if you click on the link and make a purchase. I only recommend products or services that I personally use and believe will add value to my readers. Your support is appreciated!

Mealy Machine – A mealy machine is defined as a machine in theory of computation whose output values are determined by both its current state and current inputs. In this machine atmost one transition is possible.
It has 6 tuples: (Q, q0, ∑, O, δ, λ’)
Q is finite set of states
q0 is the initial state
∑ is the input alphabet
O is the output alphabet
δ is transition function which maps Q×∑ → Q
‘λ’ is the output function which maps Q×∑→ O

Diagram –

Moore Machine – A moore machine is defined as a machine in theory of computation whose output values are determined only by its current state.
It has also 6 tuples: (Q, q0, ∑, O, δ, λ)
Q is finite set of states
q0 is the initial state
∑ is the input alphabet
O is the output alphabet
δ is transition function which maps Q×∑ → Q
λ is the output function which maps Q → O

Diagram –

Moore Machine –

1.    Output depends only upon present state.

2.    If input changes, output does not change.

3.    More number of states are required.

4.    There is less hardware requirement for circuit implementation.

5.    They react faster to inputs.

6.    Synchronous output and state generation.

7.    Output is placed on states.

8.    Easy to design.

Mealy Machine –

1.    Output depends on present state as well as present input.

2.    If input changes, output also changes.

3.    Less number of states are required.

4.    There is more hardware requirement for circuit implementation.

5.    They react slower to inputs(One clock cycle later).

6.    Asynchronous output generation.

7.    Output is placed on transitions.

8.      It is difficult to design

Share This Article
Follow:
Prabhu TL is an author, digital entrepreneur, and creator of high-value educational content across technology, business, and personal development. With years of experience building apps, websites, and digital products used by millions, he focuses on simplifying complex topics into practical, actionable insights. Through his writing, Dilip helps readers make smarter decisions in a fast-changing digital world—without hype or fluff.
Leave a review