CS201 Lab: Combinational Design

Objective of this lab:

	To verify combinational design procedures by testing designed circuits.

Preparation

	Read lab lecture notes which contains the Combinational Design Procedure.

Lab Assignments

1. Design and implement a 4-input majority detector.
   • The output is high if two or more of the inputs are high.
   • Use Karnaugh map reduction to get the simplified Boolean function.
   • Draw the circuit and simulate the circuit in LogicWorks.
   • Check if the truth table for the circuit meets the result of your experiment.
   • For your lab assignment, make sure that you follow the combinational design procedures.
     Marks will be given to each step.
   Hand-In
   • The five steps used to solve this problem.
     Note: Step 5 inclides drawing the logic diagram and implementing the test circuit in LogicWorks.

2. Design a circuit which will control LED segment "c" of a 7-Segment display.
   • See the diagram below to understand what a "c" segment is.
   • If the segment is lit, then the output should be 1. If the segment is not lit, then the output should be 0.
   • For example, for the numbers 0, 3, and 4, segment "c" should be lit;
     for numbers 1, and 2, segment "c" should not be lit; etc.
   • Design the circuit so that if someone applies a value from 10 to 15 then the LED segment does not light.

     The following guidelines apply to the 2nd part of the lab assignment:
     

   • You may only use NAND and NOT gates (it is common to have your design limited to certain gates).
   • Show all the steps of the combinational design procedure including test results.
   • Present the simplified SOP form after using the Karnaugh map reduction method.
   • Present the expression that can be implemented by using NAND and NOTgates.
   • Print out the circuit when inputs are 1, 3, 9 and 11.
   • A 7-segment display can display the digits 0 - 9 by having the appropriate LEDs turned on.

     

   Hand-In
   • The five steps used to solve this problem
     (Remember the two expressions are needed.)
   • Print out of the circuit when input is 1, 3, 9, and 11