Mealy and Moore Machines

Mealy Machines

What assumptions did you make in the design of this machine? The assumption made is that the starting point is a logic diagram and that the each function will return zero if the input list is zero.

Create a state definition table here that describes in plain English what each state in your machine means and what binary values you have assigned to represent each state

Current Next

Reset Input State State Output

1 - - A 0

0 0 A B 0

0 1 A C 0

0 0 B C 0

0 1 B C 1

0 0 C B 1

0 1 C C 0

Create tables here to display your state diagrams, state transition tables and Karnaugh maps used in your design process. (You can do this by hand if you wish.)

State Transition Diagram

Current State

A B Input 1 Next State

Anext Bnext Outputs

Y

0 0 0 0 0 0

0 0 1 0 1 0

0 1 0 0 0 1

0 1 1 1 0 1

1 0 0 0 0 0

1 0 1 1 0 0

1 1 0 X X X

1 1 1 X X X

Karnaugh Maps for the Mealy Machine

Q2Q1/Q0X 00 01 11 10

00 0 0 0 0

01 0 1 0 0

11 X X X X

10 X X X X

J2 = Q1 Q 0 X

Q2Q1/Q0X 00 01 11 10

00 X X X X

01 X X X X

11 0 0 X X

10 0 1 X X

K 2 = Q1 X

Q2Q1/Q0X 00 01 11 10

00 0 0 1 0

01 X X X X

11 X X X X

10 0 0 X X

J1 = Q 0 X

Include a picture of your Logisim design schematic #1 (Mealy machine) circuit here

Mealy Machine Circuit

Implementation of the Mealy Machine

Moore Machines

What assumptions did you make in the design of this machine? The assumption made is that the outputs only depend on the current state and that the inputs and the outputs in both designs are the same.

Create a state definition table here that describes in plain English what each state in your machine means and what binary values you have assigned to represent each state. State Input X Output

S 0 1 Z

A A B 0

B A C0 0

C0 A C1 0

C1 A C1 1

Create tables here to display your state diagrams, state transition tables and Karnaugh maps used in your design process. (You can do this by hand if you wish.)

Moore State diagram

D2

Input 000 001 011 010 100 101 111 110

00 0 0 0 0 1 X X X

01 x X X X X X X X

11 0 0 1 1 1 X X X

10 0 0 0 0 1 X X X

D0

Input 000 001 011 010 100 101 111 110

00 0 0 0 0 0 X X X

01 x X X X X X X X

11 0 0 0 0 0 X X X

10 1 1 1 1 0 X X X

Transition Table

State Input X Output

Q1Q0 0 1 Z

00 00 01 0

01 00 10 0

10 00 11 0

11 00 11 1

Include a picture of your Logisim design schematic #2 (Moore machine) circuit here

Task 4-2: Simulate Both Designs

Demonstrate that both of your circuits meet the completed design specification by describing how you tested them and what your findings were.

Both Mealy and Moore machines are synchronous and sequential in nature. The only existing difference is that the output in Moores machine is a function of the state whereas the output of the Mealys machine is a function of both the input and the state.

I tested my designs using sequential and combinational circuit testing. Sequential circuits involve the incorporation of clock with other inputs of data. The circuit has a poly parameter that determines its signature and data compression. With each clock a new signature will be calculated with the new

data and existing data and existing must registered. The results and findings obtained are as shown in the above tables.

Task 4-3: Determine Criteria and Weighting for Judging Your Designs

Using the guidelines in the Design Project Description, list your criteria and associated weights here.

Best Design Criteria

Criteria Weight Mealy Moore

Rating Weighted Rating Weighted

Reduces number of logic states 0.15 2 0.30 1 0.15

Reduces number of flip-flops 0.15 1 0.15 1 0.15

Reduces wiring 0.25 2 0.50 1 0.25

Faster output response time 0.05 2 0.10 1 0.05

Output reliability 0.20 1 0.20 2 0.40

Circuit simulation 0.20 2 0.40 1 0.20

Task 4-4: Apply the Criteria to Pick the Best Design

Describe how you applied the criteria and weighting system in the above task to pick the best design.

I applied three major criteria for selecting the correct and best state machine device for a design. These three included:

Number of inputs and outputs

The speed

Its intelligence and functionality. Under these we have: Number of product terms, type of flip-flops and number of state registers. Other factors that I considered include reliability of the output and high weight.

Which design is better based on your criteria and weighting system? The best design from the above is the Mealy FSM.

Task 4-5: Build One Design in Hardware

Build one of the designs in Hardware using the ICs available to you. If you have not already done so, label the input and output pins on your schematic to allow for easy wiring and paste the schematic in the space below. Similar to Task 4-2, come up with a testing plan that allows you to assess if your circuit meets the desired specifications and report if your test has been successful or what problems you ran into. Even if you are not able to build a working circuit, you will still get partial credit if you are able to describe how far you got and what went wrong.

I had earlier on made Moore and Mealy Machines models using 4 inputs OR gates. I then used the above criteria to develop a best design. My preferred choice was the Mealy machine as it uses fewer ICs and gates to complete the wiring process. I applied the sate diagram and confirmed that it was in perfect working conditions.

Task 4-6: Take a Photo of your Completed Hardware Circuit

Before you rip everything apart, take a photo of your completed circuit and attach it to the lab template. This will serve as a replacement for the attendance stamp that the in-person students have to get on their paper lab submission.

Hardware Lab 4: Lab Report Grade Sheet

Name: Instructor Assessment: Task Oriented

Grading Criteria Max Points Points lost

Template Neatness, Clarity, and Concision 5 Description of Assigned Tasks, Work Performed & Outcomes Met Task 4-1: Design of Synchronous Sequential Machines 22 Task 4-2: Simulate Both Designs 30 Task 4-3: Determine Criteria and Weighting for Judging Your Designs 5 Task 4-4: Apply the Criteria to Pick the Best Design 8 Task 4-5: Build One Design in Hardware 30 Self-Assessment Worksheet (The content of the self-assessment worksheet will not be graded. Full credit is given for including the completed worksheet.) (5 extra points) Points Lost Lab Score Late Lab Lab Score Self-Assessment Worksheet

Put an X in the table below indicating how strongly you agree or disagree that the outcomes of the assigned tasks were achieved. Use 5 to indicate that you strongly agree and 1 to indicate that you strongly disagree. Use NA, Not Applicable, when the tasks you performed did not elicit this outcome. Credit will be given for including this worksheet with your lab report. However, your responses will not be graded, they are for your instructors information only.

Table __: Self-Assessment of Outcomes for Hardware Lab 5: Capstone Design Project.

After completing the assigned tasks and report I am able to: 5 4 3 2 1 NA

Use classical design techniques (i.e., state diagrams, state transition tables, and Karnaugh Maps), to design a synchronous sequential machine starting with a functional specification. X Make assumptions to complete an incomplete functional specification. X Write a complete functional specification. X Build, and debug a synchronous sequential machine. X Develop reasonable engineering criteria for comparing different designs. X Apply engineering criteria to select a best design. X Write below any suggestions you have for improving this laboratory exercise so that the stated learning outcomes are achieved.