An Introduction to Formal Languages and Automata, 7th Edition

A.3 MOORE MACHINES

Moore machines differ from Mealy machines in the way output is produced. In a Moore machine every state is associated with an element of the output alphabet. Whenever the state is entered, this output symbol is printed. The output is produced only when a transition occurs; thus, the symbol associated with the initial state is not printed at the start, but it may be produced if this state is entered at a later stage.

DEFINITION A.2

A Moore machine is defined by the sextuple

$$M=(Q,\Sigma ,\Gamma ,\delta ,\theta ,q_0),$$

where

1. Q is a finite set of internal states,
2. Σ is the input alphabet,
3. Γ is the output alphabet,
4. δ: Q × Σ → Q is the transition function,
5. θ: Q →Γ is the output function,
6. q₀ ∈ Q is the initial state.

The machine starts in state q₀, at which ...