# Need Someone to check my transition table and state diagram

#### HCN1996

Joined Nov 29, 2015
25
I am a bit confused as to how im supposed to do numbers 2 and 3 on my assigned homework. My completed HW is below

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#### WBahn

Joined Mar 31, 2012
26,398
You say that you haven't covered sequential circuits as all in class, yet this assignment is due on Wednesday.

Color me suspicious.

Look at your inputs to your 2-to-4 decoders. Is the '0' or the '1' input the lsb? Usually the '0' is the lsb. Which signal, 'A' or 'B', corresponds to the lsb (of those two). Ask the same question for the second layer.

#### HCN1996

Joined Nov 29, 2015
25
You say that you haven't covered sequential circuits as all in class, yet this assignment is due on Wednesday.

Color me suspicious.

Look at your inputs to your 2-to-4 decoders. Is the '0' or the '1' input the lsb? Usually the '0' is the lsb. Which signal, 'A' or 'B', corresponds to the lsb (of those two). Ask the same question for the second layer.
good catch on the decoders. Im not sure why I put them in that order.

#### WBahn

Joined Mar 31, 2012
26,398
Your problem #2 is a Mealy machine. Look that up in your text and see if that helps. There are probably some examples that are worked.

#### HCN1996

Joined Nov 29, 2015
25
Your problem #2 is a Mealy machine. Look that up in your text and see if that helps. There are probably some examples that are worked.
We do not have a textbook. I will try to figure out a better start to the table. It is the 1/0, 1/1, 0/0, and 0/1 between the states that throws me off. I have never seen that before and he as not shown us an example in class. He briefly drew those notes in 10 minutes on the 25 and thats all the background I have in this stuff.

#### JoeJester

Joined Apr 26, 2005
4,390
There are over 36,000 results on google for +"mealy machine"

#### HCN1996

Joined Nov 29, 2015
25
anyone?

#### HCN1996

Joined Nov 29, 2015
25
There are over 36,000 results on google for +"mealy machine"
would you mind looking over what I have now? I have since changed all Q0 outputs to 0 and adjusted the state diagram to show that.

#### HCN1996

Joined Nov 29, 2015
25
this is what I need to be checked.

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#### JoeJester

Joined Apr 26, 2005
4,390
My question would be, if Q0 and/or Q1 remains in the initial condition (0), would it even show up on a mealy diagram?

#### HCN1996

Joined Nov 29, 2015
25
My question would be, if Q0 and/or Q1 remains in the initial condition (0), would it even show up on a mealy diagram?
im not sure, my professor has never taught that. Is it wrong? are you saying since q0 is always 0 it shouldnt be there?

edit: im not sure what you are saying ha

#### HCN1996

Joined Nov 29, 2015
25
My question would be, if Q0 and/or Q1 remains in the initial condition (0), would it even show up on a mealy diagram?
are you referring to the table, diagram, or both?

#### JoeJester

Joined Apr 26, 2005
4,390
If the next state (1) never occurs why would one include it? On the other hand, it might be an exercise in mealy with zero practical usage in real life.

on edit:

I looked at the diagram and saw that two flip flops did not change state.

#### HCN1996

Joined Nov 29, 2015
25
If the next state (1) never occurs why would one include it? On the other hand, it might be an exercise in mealy with zero practical usage in real life.
Im thinking it is just an exercise with no practical usage. It's a freshman CE class and he just introduced it. He has not even mentioned that it is called a mealy machine.

#### HCN1996

Joined Nov 29, 2015
25
If the next state (1) never occurs why would one include it? On the other hand, it might be an exercise in mealy with zero practical usage in real life.

on edit:

I looked at the diagram and saw that two flip flops did not change state.
with that being said is my table and diagram correct even though some of it might not be necessary?

#### JoeJester

Joined Apr 26, 2005
4,390
with that being said is my table and diagram correct even though some of it might not be necessary?
I don't know what your instructor wants. I'll let @WBahn weigh in with his opinion as he is an instructor.