IEC 61162-1

IEC 61162-1 is the international standard for the single-talker, multiple-listener serial interface that carries NMEA 0183 navigation sentences between marine electronics at 4800 baud (38400 for AIS). It defines the electrical interface, sentence formatting, and the approved sentence set (for example GGA, RMC, VTG) used to pass GNSS position, heading, depth, and AIS data among bridge equipment. The current edition is IEC 61162-1:2016; it is the technical basis equipment makers cite for NMEA 0183 conformance.