nmea

README

mab-go/nmea

A Go library for parsing NMEA 0183 sentences. Verify checksums, extract typed fields, and decode sentence types like GPGGA and GPGLL into structured Go values.

---

Quick Start

import (
    "fmt"
    "log"

    "github.com/mab-go/nmea/sentence/gpgga"
)

fix, err := gpgga.Parse("$GPGGA,174800.864,4002.741,N,07618.550,W,1,12,1.0,0.0,M,0.0,M,,*70")
if err != nil {
    log.Fatal(err)
}
fmt.Printf("Lat: %f %s, Lon: %f %s\n", fix.Latitude, fix.NorthSouth, fix.Longitude, fix.EastWest)

---

Installation

go get github.com/mab-go/nmea

Requires Go 1.26 or later.

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Supported Sentences

Package	Sentence	Description
sentence/gpgga	GPGGA	GPS fix data: time, lat/lon, fix quality, satellite count, HDOP, altitude
sentence/gpgll	GPGLL	Geographic position: lat/lon, fix time, data status, mode
sentence/gpgsa	GPGSA	GPS DOP and active satellites: selection mode, fix mode, PRN list, PDOP/HDOP/VDOP

The sentence package provides lower-level building blocks usable with any NMEA 0183 sentence:

• VerifyChecksum — validates the *XX checksum on a raw sentence string
• SegmentParser — splits a sentence into typed fields (AsFloat64, AsInt16, AsString, AsNMEATime, and more)
• NMEATime — UTC fix time as hour/minute/second/millisecond (no float precision loss)

---

Development

First-time setup (installs golangci-lint, goimports, gocyclo into ./bin):

make setup

Then:

make test        # Run all tests (with -race by default)
make test:cover  # Tests + HTML coverage report
make lint        # golangci-lint
make fmt         # goimports

Run make help for the full list of targets.

---

License

MIT. See LICENSE.

Documentation

Overview

Package nmea contains "sub-packages" that comprise a toolkit for interacting with NMEA data streams and NMEA data.