University of North Texas Department of Electrical Engineering

EENG 2910 Project III – Digital System Design Assignment – 2

Instructor: Rani

 

Multiplexer and Demultiplexer

Due Date: 02/06/2019

 

Introduction

 

Combinational logic circuits are circuits whose outputs depend only on the present value of their inputs. The lecture on “Combinational Logic Design” introduced you to some of the common combinational logic circuits.

 

For your second assignment, you are required to Design, Implement, and Test an 8-bit wide 8- to-1 multiplexer (MUX) and 8-bit wide 1-to-8 demultiplexer (DEMUX).

 

Design 8X1 MUX using 4X1 MUX which is designed using 2X1 MUX (Behavioral Model) component tested in class.

 

Design 8-bit wide 1X8 DEMUX using 1X4 DEMUX which is modelled in behavioral.

 

 

Recommended Design Procedure

 

1. Find the number of input variables and the number of required output variables. Assign them meaningful
2. Create a truth table that defines a relationship between inputs and
3. Obtain a simplified Boolean function for each
4. Draw the logic
5. Implement your design using VHDL
6. Test your design by creating a test bench
7. If possible, load your circuit to the board and test it (not required but could be a good practice – extra credit could be given if you show output to instructor).

 

 

Report:

 

Submit a soft copy of your report on CANVAS. Due date for this assignment is on 02/06/2019, 2:30PM. Please save the copy of your project in your flash drives. In instructors asks you to show your outputs, please be ready either beginning of the class or end of the class. Make sure that your report includes the following:

 

1. A cover page with your name, the name of the project, date, etc. (5 pts)

 

2. An introduction – what are the goals of the project? What is an adder? What is the use of an adder? How you are going to design 8-bit adder These are sample questions that you should attempt to answer in the introduction. (10 pts)

3.       Theory of operation and explanation of the design (10 pts)

Give a brief discussion of the theory of operation, including schematics and equation used, etc. This is of importance for the design-oriented labs and mini-projects. You should also explain the schematics involved in your design in detail.

 

4. Experimental results: (60 pts including the section on “Theory of Operation”)
   • Brief description of the lab
   • Schematics of the circuit (from Xilinx schematic entry tool). Put your name and date on each
   • Simulated
   • Discussion of the results indicating that the circuit functions It is not good enough to just give the simulated waveform. It is up to you to show that this waveform corresponds to what you expect (do not say “the simulation shows that the circuit works properly”). You need to make it clear to the reader that the circuit works properly! One convenient way is to use some of the entries in the truth table in your test bench, indicating that for each entry/input the corresponding values/outputs given by the logic simulator correspond to what is displayed in the table.
   • All figures/schematics in the report must have a figure number, title, and referenced in the body of your

o

5.        Conclusion: (10 pts)

The conclusion should contain a summary of the results. Are the goals of the lab fulfilled? If not, explain why.

 

6.        References: (5 pts)

List all the references used for the project and refer to them in the body of your report.