Note: As with the work for the previous lab, the following problems are to be done on paper collaboratively. Everyone should work in a group of two (preferred) or three students; within a group, each person should take responsibility for leading discussion for some of the problems.
Steps for this Lab:
Inputs Output A B C D ------------- ------ 0 0 0 1 0 0 1 0 0 1 0 1 0 1 1 0 1 0 0 0 1 0 1 1 1 1 0 0 1 1 1 1Explain briefly why your circuit is correct.
Try to do this with a minimum number of gates. For instance, if you were to use the straightforward method, as was done in the previous lab, your circuit might require six 4-input AND gates, one six-input OR gate, and 12 NOT gates. Using some Boolean equivalences to minimize logic expressions, design this circuit with a reduced number of gates.
This circuit requires four inputs, referred to as a1, a2, b1, and b2. a1 and a2 represent a 2-bit number, as do b1 and b2. The output will be true if the decimal number represented by the pair a1a2 is less than the decimal number represented by b1b2.
This document is available on the World Wide Web as
http://www.math.grin.edu/~walker/courses/211/labs/lab1.html