7 February, 2000
Logic design -- Getting the homework done
- Truth tables
- Cannonical sum-of-products
- Algebraic simplification
Everyone's favorite example -- the seven segment display
_ _ _ _ _ _ _ _ _ _ _ _
| | | _| _| |_| |_ |_ | |_| |_| |_| |_ | _| |_ |_
|_| | |_ _| | _| |_| | |_| _| | | |_| |_ |_| |_ |
Laws of Boolean Algebra
Commutativity |
x + y = y + x |
x y = y x |
Associativity |
x + (y + z) = (x +
y) + z |
x (y z) = (x y)
z |
Distributivity |
x (y + z) = x y +
x z |
x + y z = (x + y)
(x + z) |
Identity |
x + 0 = x |
x 1 = x |
Idempotency |
x + x = x |
x x = x |
Annihilation |
x + 1 = 1 |
x 0 = 0 |
Complement |
x + x' = 1 |
x x' = 0 |
Involution |
(x')' = x |
de Morgan's law |
(x + y)' = x' y' |
(x y)' = x' + y' |
absorption |
x + x y = x |
x (x + y) = x |