TI2/Rechnerarchitektur-Tutorium, 15.12.2016

Nachbesprechung

Carry-Lookahead

1. ü4

ü1 = 0

ü2 = g1 ∨ p1ü1 = g1

ü3 = g2 ∨ p2ü2 = g2 ∨ p2g1

ü4 = g3 ∨ p3ü3 = g3 ∨ p3(g2 ∨ p2g1)=g3 ∨ p3g2 ∨ p3p2g1

2. gi, pi

a4..1 = 1010

b4..1 = 0110

g4..1 = 0010 gi = ai ∧ bi

p4..1 = 1100 pi = ai ⊕ bi

Carry-Lookahead

3. si

si = pi ⊕ üi

ü4..1 = 1100

p4..1 = 1100

s4..1 = 0000