A communication network digital message format is provided in which on message start signal has a logic "1" value for two bit intervals to provide improved noise immunity in transmission of a message over a network medium. The start signal is followed by a control bit one logic value of which designates...http://www.google.com/patents/US4644547?utm_source=gb-gplus-sharePatent US4644547 - Digital message format for two-way communication and control network
