NMEA 2000

The NMEA 2000 Data Interface Standard was developed by the NMEA® (National Marine Electronics Association of America). It is an international standard to enable equipment from many different manufacturers to be connected together and share information.

NMEA 2000DeviceNetCAN busProtocolsNMEA 2000ProtocolsDeviceNet

The NMEA 2000 standard was specifically intended to allow for a whole network of marine electronics from any manufacturer to communicate on a common bus via standardized message types and formats.

NMEA 2000 offers significant improvements over NMEA 0183, most notably in speed and connectivity. Up to 50 units can simultaneously transmit and receive on a single physical bus at any one time, with each node being physically addressable.

This disciplined multiple-talker, multiple-listener data network is therefore a significant improvement when compared to the NMEA 0183 single-talker, multiple-listener (simplex) serial communications protocol.

NMEA 2000 utilizes a single backbone which compatible equipment connects to using a spur. Data and power are carried within the backbone. Devices that have a low power draw can be powered from the network, although high current equipment will need to have a separate power connection.

NMEA 2000 and DeviceNet interoperability

Electrically, NMEA 2000 is very similar to, and compatible with, the Controller Area Network ("CAN bus") technology known as “DeviceNet”. However, NMEA 2000 includes specific messages for the marine environment. Due to their electrical compatibility, NMEA 2000 devices and DeviceNet devices can co-exist on the same physical network, and can also use the same cables. Typically, the DeviceNet cables used in NMEA 2000 networks are known as “Micro-C”, or sometimes just “Micro”.