Re: ALU, negationx, y, add16 off by one?

Posted by rogerdodger91 on Dec 11, 2011; 4:26pm
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/ALU-negationx-y-add16-off-by-one-tp3564869p3577592.html

I have a working ALU.

I just now have two ALUs.

One that does an off by one subtraction and on that give you a true valid subtraction answer.. They both give the same AND bitwise results results. I understand twos complement. I know that since you cant have a +0, and -0 is the reason why my method might be wrong. I just want to know why we dont necessarily us my proposed fixed with in place of the other one.

Whats wrong with my ALU basically theoretically speaking.