"network topology" for NMEA 0183 protocol

Discussion in 'General Electronics Chat' started by kender, Jul 29, 2012.

  1. kender

    Thread Starter Senior Member

    Jan 17, 2007

    What "network topology" is NMEA 0183 typically used in? Is it intended only for point-to-point wiring?

    In the standard.

    • Communication is asynchronous. Talkers (remote devices) can transmit whenever they wish. NMEA 0183 protocol doesn't define collision resolution.
    • There are predefined Talker IDs. But what to do if there are 2x identical depth sounders? The sentences don't have fields for numeric addressing.
    • Standard suggests RS-422 and RS-232 for electrical interface. These are intended for point-to-point communication.

    Any suggestion, insight or reference is really appreciated!

    - Nick

    P.S. There is NMEA 2000, which runns on a multidrop CAN bus. There are also NMEA 0183 to Ethernet bridges. I'm aware of them.
  2. HDowns

    New Member

    Nov 24, 2010
    Yes, this is point-to-point network. NMEA 0183 devices work as master. NMEA 0183 devices can't be addressed without additional hardware.