Computer Org. 2019.01.25

Seite 1

Qwickly Attendance #: 9412

Boolean Algebra and Digital Logic Gates

We call propositions 'variables'

Variables can only have values 1 or 0 instead of True / False

George Boole, 1815-1864

Some laws of Boolean Algebra:

Commutative laws: a+b = b+a. ab = ba = b*a

Distributive laws: a+(bc) = (a+b)(a+c), a(b+c) = ab+ac

Identity laws: A +0 = A . A *1 = A

Complement laws: A + A ̅ = 1. A * A ̅ = 0. A -1 = A ̅ <<< A way to invert the logic. A-1 is like "not A OR 1"

Binary Logic:

There are only High (5 volts) and Low (0 volts) signals

High is interpreted as 1 (true)

Low is interpreted as 0 (false)