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1. Building Boolean Logic

Before you read this section, you need to understand about basic logic functions, boolean algebra and truth tables - we have a section on that HERE.

From that section, this is a summary of the logic operations that show logic gate, truth table and boolean expression. For this course you need to be able to move between gate layout, truth table and boolean expressions. This section will help you practice.

Boolean algebra and gate symbols
Symbol Type of Logic Truth Table Equivalent Statement
Input A, Output QNOT gate NOT $$ Q = \bar A $$
Inputs A, B, Output QAND gate AND $$ Q = A.B $$
Inputs A, B, Output QOR gate OR $$ Q = A + B $$
Inputs A, B, Output QXOR gate XOR XOR truth table
$$ Q = A \oplus B $$
Inputs A, B, Output Q NAND $$ Q = \overline{A.B} $$
Inputs A, B, Output Q NOR $$ Q = \overline{A + B} $$

 

 

Challenge see if you can find out one extra fact on this topic that we haven't already told you

Click on this link: What is computer logic