Encoder having combination logic circuit and method for using the same

PURPOSE: To provide an 8B/10B encoder for supplying one output of the 8B/10B command code outputs which are noncompolements of a pair of inverse disparities in response to an RD and a selected command input. CONSTITUTION: The 8B/10B encoder has a combination logic circuit, and includes a means in response to both input (n) digital bits, which are a specific set to generate (a) the value of execution disparity and (b) one of a 1st and a 2nd output digital codes in the combination logic circuit. The 1st and the 2nd output digital codes mutually do not have a complement from.