9. Final Design Project

9.1. Objectives

This two-meeting design project is designed to provide a capstone experience for the laboratory portion of ELEC 2210. The objectives of this experiment include the following:

  • Reinforce the concepts learned throughout the semester
  • Introduce students to design
  • We will continue to develop professional lab skills and written communication skills

9.2. Required SFPs and Customized Programs

  • 3-wire I-V analyzer
  • Digital Multimeter
  • Digital Writer
  • Signal Express program for base-collector current transfer characteristics
  • Labview vi program provided for forced Vbe measurements

9.3. Available Components

Please see Parts. Check with your GTA for specific parts questions. They will try to accomodate your needs.

9.4. Introduction

Many electronic systems have the nature of a finite state machine (FSM). These are systems in which a desired output results from a certain sequence of inputs. For example, pressing a certain code on a keypad causes a door to unlock.

In this project, you will design a FSM that will turn on a fan and light when the correct code is entered, but will sound an alarm if the incorrect code is entered.

This is a design project. One consequence of this is that there is no one right solution. There are various ways to achieve the desired result, and you will need to decide on your own how to proceed. For example, you may use a BJT or a MOSFET to turn on a fan. Either one is acceptable, but once you choose, other aspects of the design will be affected.

9.5. Project Statement

In this project, you must design a FSM that will turn on a fan and an LED when a correct code is entered, but will produce an audible sound (“alarm”) if an incorrect code is entered.

  1. Set DIO7 to DIO4 of the Digital Writer to store a random 4 bit code given by your GTA. Use DIO7 for MSB and DIO4 for LSB.
  2. Set DIO3 to DIO0 initially all to 0.
  3. Toggle DIO0 on and off to reset the circuit. An LED will begin blinking at a rate of approximately twice per second and will remain blinking until four code bits are entered. Enter a code of 4 bits, MSB first, as follows:
  4. Set DIO1 to 1 or 0 (next bit of your code) in the Digital Writer
  5. Toggle DIO2 on and off in the Digital Writer to enter this bit.
  6. Perform (4)-(5) three more times until four code bits are entered.

At this point, either a fan and LED will come on (correct code entered), or an audible sound will be produced by a loudspeaker (incorrect code entered). The LED can be the same one that was blinking, but it should now be on steadily. Alternatively, the blinking LED must go off, and another LED must come on. At any time, the user can toggle DIO0 on and off to reset the circuit and start over entering the code.

You will be given your own individual codes in lab the day of your demonstration. You may use any of the circuitry on the ELVIS II. You can use any of the IC chips and components used during the semester, as well as any others that you are provided.

9.6. Lab Exercise

You will be allowed to work in the lab only during your regularly scheduled section meeting time. This is not an “open lab” type of project. Of course, design work, computer simulation, etc. can be conducted any time you want. Your lab time will be most productive if you come prepared with schematics and ideas to test.

You can purchase your own breadboard and some chips at the Scientific Supply Store if you so desire, but with proper preparation, it should not be difficult to build the entire design during the lab period with the provided components.

You must demonstrate your working circuit to your GTA before leaving lab.

You will have access to all of the components and equipment that were used throughout the semester, a supply of 74LS73 dual JK flip-flop chips, as well as a supply of 74198 shift register IC’s in the lab. See the lab web site for datasheets or google them.

9.7. Report

Your report is due in your GTA’s mailbox as posted on the lab website.

Your report should include both a function-block diagram, a package / pin-level schematic of your circuit and Multisim simulation results.

You should also explain how the circuit works, and show the details of your design process, such as FSM state tables, truth tables, etc.

You should Email your GTA the Multisim simulation files.