A Question About Building A Circuit That Complements a num

[transgalactic]

i need to build a circuit that its input is a 4 digit binary number
and its output is the complement to 2 of this input number

i need to implement this circuit only using FS and NOT components.

i know that in order change a number into a complement of 2
we need to keep the first three digits as they were
and flip the value on each digit for the rest of the number.
(X) -xor opearation

y(+)0=y

y(+)1=y'

thats how we flip the numbers so i dont no why to use the FS component

i will live the first 3 inputs as they were and the last one will have this operation
y(+)1=y'

lol i can accomplish this using one XOR gate
but i think that i made a mistake regarding this sort of solution

am i right??

 

[laktronics]

Re: A Question About Building A Circuit That Complements a n

Hi,
Use the NOT gates first and get the 1's complement. Then add 1 to it to get 2's complement, does your FS block will hep to do the addition?

Regards,
Laktronics