CSCI 232 Lab 2

Combinational Logic

 

Date Due: 8 February 2012

 

This assignment will give you practice with the 7400 family of combinational circuits.  You will verify some of the rules of logic we discussed in class.

 

Note: Before you build any circuit using the CADET, you are to first simulate your design using LogicWorks and verify that it performs the desired operations.  You are to print out your LogicWorks schematic and turn that in.  Be sure to include your name, the course, the date, and the lab number in a box on your schematic.

Each person is to do their own circuit design for this lab.  You should demonstrate to me that your design works in LogicWorks before moving on to actually implementing any circuit.  Once you start to actually implement the design, you may work in teams of two, choosing one design to implement.  Do not turn the power on to the CADET until you have double checked your wiring!  After you have tested and implemented each circuit, you are to demonstrate it to me for grading.  At the end of the lab, you should return all wires and IC’s to the appropriate storage places, and put the CADETs back on the shelves.

 

  1. Using a minimal number of NOR gates to implement the AND, OR, and NOT functions simultaneously.  You should use two switches as input, and should use an LED as output for each of the three functions: AND, OR, and NOT.  When you have this circuit working, demonstrate it to me before moving on to the next part.

 

 

  1. Build a logic circuit to verify DeMorgan’s law: (XYZ)’ = X’ + Y’ +Z’.  You should implement both sides of the equation separately and have the outputs of each go to a separate LED.

 

 

  1. Verify by wiring a logic circuit that X+YZ = (X+Y)(X+Z).  You should build separate circuits to implement each side, and have each one send its output to a separate LED.

 

  1. Using a minimal number of NAND gates, implement a circuit that turns the bottom left segment of a 7 segment display on for the appropriate binary inputs.  Your circuit should use 4 input switches and display its output on a LED.