Nmea 0183 Codes Jun 2026

| You need | Use sentence | |----------|---------------| | Position, time, speed | RMC | | Detailed fix quality | GGA | | Depth | DPT | | Water temp | MTW | | Wind | MWV | | AIS target | VDM | | COG & SOG only | VTG | | Autopilot cross-track error | APB |

: Starts with * followed by a two-digit hex value to verify data integrity. End : Ends with a carriage return and line feed .

A typical sentence, or "code," begins with a dollar sign ( $ ), followed by a talker identifier (two letters indicating the device type, such as GP for GPS or SD for Sounder), and a sentence identifier (three letters defining the data content). This is followed by a comma-delimited list of data fields and ends with a checksum. nmea 0183 codes

All sentences begin with a $ (or sometimes ! ). Address Field: The next five characters identify the data.

: Transmits current depth in feet, meters, and fathoms. ZDA (Time & Date) : UTC time, day, month, and year. 4. Technical Specs for Setup | You need | Use sentence | |----------|---------------|

When a chart plotter fails to show depth, the technician taps into the data stream. If they see the SDDBT codes flowing, they know the transducer is working and the cable is intact; the fault lies in the plotter's settings. If they see scrambled characters, they suspect a "baud rate" mismatch—a collision of speeds. If they see nothing, they hunt for a severed wire.

This structure—rigid, predictable, and lightweight—was designed for a world of low bandwidth. In the early days of marine electronics, transmission speeds were often limited to 4800 baud. NMEA 0183 needed to be efficient. It sacrificed the complexity of binary data for the universality of text, ensuring that a computer built in 1990 could theoretically parse data from a sensor built in 2024. This is followed by a comma-delimited list of

: A three-letter code (e.g., GGA , RMC ) defining the data type.