Thanks all for the help. It is nice to have a place where a person can ask these types of questions and not get a lot of flack for not knowing something as I see in some forums.
I have enough information to be able to study the switch and its uses.
Read bcd
bcd complememtry
Real hexadecimal
Complementry hexadecimal
Gray code.........The reflected binary code, also known as Gray code after Frank Gray, is a binary numeral system where two successive values differ in only one bit.
The reflected binary code was originally designed to prevent spurious output from electromechanical switches. Today, Gray codes are widely used to facilitate error correction in digital communications such as digital terrestrial television and some cable TV systems.