COMP 273 Lecture Notes - Lecture 3: Xor Gate, Bell Labs, Or Gate

• School: McGill University
• Department: Computer Science (Sci)
• Course: COMP 273
• Professor: Piotr Przytycki

Document Summary

In lectures 1 and 2, we looked at representations of numbers. For the case of integers, we saw that we could perform addition of two numbers using a binary representation and using the same algorithm that you used in grade school. I also argued that if you represent negative numbers using twos complement, then you can do addition with negative numbers as well. In lecture 4, we will see how to implement the addition algorithm using circuits. Before we can do so, we need to review some basic logic and use it to build up circuits. Let a and b be two binary valued variables, that is, a, b each can take values in {0, 1}. If we associate the value 0 with false and the value 1 with true, then we can make logical expressions using such binary valued variables. We make such expressions using the binary operators and,