Re: ALU Implementation

Posted by WBahn on Jul 24, 2021; 2:32pm
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/ALU-Implementation-tp4036186p4036189.html

What f does has nothing to do with how the input and output signals are modified by the other control bits.

The zx anf nx bits make some changes to the 16-bit x-input resulting in a 16-bit signal, call it Fred, and that signal is sent to the adder and the ander. The f input controls which of the two 16-bit outputs of those two is used for further processing.

Remember that you have a part that is specifically designed to let a 1-bit control signal choose which of two 16-bit signals to pass to its output.