How to develop a binary code

Answer 1

https://www.sololearn.com/learn/4401/?ref=app

Answer 2

8421 is a good method
if you want to make a code of say 3 then...it would be 0011 ...just sum of last two.
similarly if want to make binary of 4
then 0100.

Answer 3

A bit Off-Topic, but why are most questions asked harder to read than machine code for an unknown cpu? I simply don't get what you are asking :/