Re: ALU Help

Posted by ybakos on Sep 14, 2016; 5:06am
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/ALU-Help-tp4030242p4030249.html

When f is 0, then take x AND y ("bitwise AND" is a logical AND, it is the AND you know).
When f is 1, then take x plus y (arithmetic sum).

snowkel wrote

zx = 0, this means that x (0100) is not zeroed.
nx = 0, x is not negated
zy = 1, y is zeroed (0000)
ny = 1, y is negated (1111)

What is x now? 0100
What is y now? 1111

f = 0, so x AND y

0100 AND 1111 = ?