COMP 150 Gates Homework

60 points

This is an individual assignment, not a pair assignment.

This semester, we will use:  which runs in the cloud

or this one, which is also pretty cool:

Or, you may write it on paper and scan it before uploading into Sakai.  But really, don't do that.

  1. (10 points) Create circuit diagram for the Boolean expression (AB + C)D.
  2. (10 points) Write a Boolean expression for the output of this circuit:
    Description: circuit diagram
    Remember wires only connect at dots. 
  3. (10 points) Write a Truth Table for the Boolean expression (A+B')C.  Include columns for the inputs A, B, and C.  Please include a column in your truth table for the output of each intermediate expression.  Include rows for all 8 combinations of input variables.
  4. (10 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 (the majority) are set to 1.   There are eight possible combinations for the input settings. Please give a truth table which lists rows for all eight input combinations along with the output setting for each case.
  5. (10 points)  Write a Boolean expression for the output of the three-way majority circuit from problem 4. 
  6. (10 points)  Construct a circuit which implements the three-way majority function discussed in the previous two questions.  You may use AND and OR gates with more than 2 inputs to make it easier.

Submit  in Sakai.   No log required.