Question

What are gray codes and bcd? when are they preferred?

Answer 1

Gray code encoders, also known as reflected binary code encoders, produce only a single bit change at each step, which can reduce encoder communication errors.

Gray code encoders are an option for serial or parallel encoder communication protocols.
Gray code encoder output is commonly used in high speed applications or those with large amounts of signal noise resulting in missing signal data when reading binary data.
Short for Binary Coded Decimal, BCD is also known as packet decimal and is numbers 0 through 9 converted to four-digit binary. ... However, in binary, 25 is represented as 11001. BCD was used in some of the early decimal computers, as well as the IBM System/360 series systems.