Contents:

• Overview
• Internet Requirements
• Practice Problems
• Problems to be Submitted
• Extra Credit

Topic: Gates and Circuits
Related Reading: Ch. 4
Due: 8pm Monday, 27 September 2004

For this assignment, we will rely heavily on the Logic Simulator software demonstrated in class. You will need to have an external Internet connection to run this software.

• Exercise 33 of Ch. 4 (p. 118); answer in back of text

• Exercise 39 of Ch. 4 (p. 118); answer in back of text

• Exercise 55 of Ch. 4 (p. 119); answer in back of text

• Exercise 57 of Ch. 4 (p. 119); answer in back of text

• Exercise 59 of Ch. 4 (p. 120); answer in back of text

• Exercise 61 of Ch. 4 (p. 120); answer in back of text

• Complete Lab 7.1 associated with the Logic Simulator software. This lab walks you through the use of their Logg-O software, which we will be using for this assignment.

• Complete Lab 7.2 associated with the Logic Simulator software. This lab lets you start building some interesting circuits (some of which may look familiar from lecture).

1. (4 points)

   Complete exercise 56 of Ch. 4 (p. 119), however instead of drawing your answer, use the Logic Simulator software to construct the circuit. Save your circuit in a file titled circuit to be submitted.

2. (4 points)

   Exercise 60 of Ch. 4 (p. 120). Please include a column in your truth table for the output of each intermediate gate within the circuit as well (as done on pp. 106-107, and in the solution to practice Exercise 59 in the text).

   You may do the problem by hand or you may wish to use the Logic Simulator as a tool. In any event, the only thing which must be submitted for this problem is a writeup of the truth table.

3. (4 points)

   Exercise 62 of Ch. 4 (p. 120). Again, please include a column for the output of each intermediate gate within the circuit.

4. (4 points)

   A three-way majority circuit is one with three inputs and a single output which is set to 1 whenever two or more of the inputs are set to 1.

   There are eight possible combinations for the input settings. Please give a truth table which lists all eight combinations along with the output setting for each case.

5. (4 points)

   Construct a circuit which implements the three-way majority function discussed in the previous question, while using the Logic Simulator software. After testing its validity, save it in a file named "majority" for submission.

Please type your answers to questions B, C and D in a single document to be submitted electronically. Submit the Logic Simulator files for problems A and E as well. Please see details about the submission process.

Interestingly, any given boolean function can be calculated by a circuit consisting solely of NAND gates.

• Create a circuit, using only NAND gates, which has the same overall behavior as a NOT gate. That is, your circuit should have one input switch and one output light, and the light should be on precisely when the switch is off. Save your circuit in a file named "ExtraNot" to be submitted.

• Create a circuit, using only NAND gates, which has the same overall behavior as an AND gate. That is, your circuit should have two input switches and one output light, and the light should be on only in the case with both input switches are on. Save your circuit in a file named "ExtraAnd" to be submitted.

• Create a circuit, using only NAND gates, which has the same overall behavior as an OR gate. That is, your circuit should have two input switches and one output light, and the light should be on so long as at least one of the input switches is on. Save your circuit in a file named "ExtraOr" to be submitted.