How can I show a tied-off output on a digital logic schematic?

Question

Combinational circuit that takes 3 bit binary numbers as input and its output is 2's complement of even number and 1's complement of odd number

Hey, I have this assignment that I'm supposed to do. I've tried it myself but I'm stuck. Please help me complete if my process is right.

First, i made a truth table with 3 inputs and 4 outputs:

On Drawing the K-Maps, i found that:

A=x'y'z'
B=x y'z' + x'y + x'z
C=y'z+yz'
D=0

I then drafted out the circuit diagram, but i'm not sure how to show D's diagram since D=0

How do i show the D circuit?

Since the three inputs have no effect on D you can just tie it to zero. It would be even better to just leave it out. btw I didn't look at the correctness of the equations. — Marco
– Marco, Commented Jan 20, 2016 at 16:45
You have mistakes in truth table, and so in equations and on schematic. Check once again how to calculate 2's and 1's complement. — Jakub Rakus
– Jakub Rakus, Commented Jan 20, 2016 at 17:00

Aadarsh · Accepted Answer · 2016-01-20 17:10:07Z

The K-map simplification seems to be wrong.

1 Answer 1