How to assemble the Demux?

Posted by GustavoB on
URL: http://nand2tetris-questions-and-answers-forum.52.s1.nabble.com/How-to-assemble-the-Demux-tp3814846.html

I've easily assembled the Mux after the cannonical representation stuff, but now i'm stuck on the Demux. It's the inverse process and i have no clue on how to do it.

I was thinking about using the x function, like this:

s a
0 0 - 0
0 1 - 0
1 0 - 1
1 1 - 1

The first column would be the selector, making the signal flow to the right place of the row:

sel| a   b
0   | in  0
1   | 0  in  (2 Dimensions Table)

With that x function, I can select the row:

sel    | a     b
0 - 1 | (i0) (i1)

But I'm stuck when It comes on representing a second dimension like the 2 dimensions table.

I'm also not very sure about that theory. Some time later, I've thought about using the a input as the demux input, the I've searched this about these functions:

(Xor)                (Equivalence)
s a                    s a
0 0 -0               0 0 -1  
0 1 -1               0 1 -0
1 0 -1               1 0 -0      
1 1 -0               1 1 -1       

I feel they can help me to represent that bidimensional matrix. Can you help me?

Thanks in advance.