Generaly when designing mealy or moore ckts when to pick which?

[trickae]

1. The problem statement, all variables and given/known data

Not really a HW question but say we follow the steps in converting a state diagram down to its excitation table - how do we determine whether the best ckt implementation would be best implemented with either a mealy or a moore system

2. Relevant equations

mealy :
state equation : Q = f(present state, current inputs)
output equation: Z = h(present state, current inputs)

Moore :
state eqaution : Q = f(present state, current inputs)
output equation: Z = h(present state)


3. The attempt at a solution

1) granted we 're given a function for a truth table
f(A,B,C,D...,etc) = logic function

2) we convert it into a state / excitation table depending on the kind of flip flops we want to use


D flip flop:

q Q | D
0..0 0
0 1 1
1 0 0
1 1 1

not Q = C' . d + Q.D
or Q = D

T flip flops

q Q | T
0 0 0
0 1 1
1 0 1
1 1 0

Q = Tq' + T'q

J/K flip flops

q Q | J K
0 0 0 x
0 1 1 x
1 0 x 1
1 1 x 0

let x = don't care values

Q = Jq' + K'q

[berkeman]

I generally use the Moore structure, and I think it is the more commonly used. I think you would only use the Mealy structure if you needed to propagate input changes through the structure a clock earlier than you get with the Moore.