Encoding in which data and clock signals are combined to form a single self-synchronizing data stream, one of the two bits, i.e., '0' or '1', is represented by no transition at the beginning of a pulse period and a transition in either direction at the midpoint of a pulse period, and (c) the other is represented by a transition at the beginning of a pulse period and a transition at the midpoint of the pulse period. Note: In differential Manchester encoding, if a '1' is represented by one transition, a '0' is represented by two transitions, and vice versa.