garmin-parser

Garmin USB binary protocol parser for nodejs / nwjs

Install

npm install garmin-parser --save

Features

Parser written by using of Garmin Device Interface Specification May 19, 2006 (It's a latest documentation which i found)

At this moment only session start and PVT data parsing is available. Tested on:

Montana 650t
Oregon 450

Another features and more detailed docs will come soon.

How to use

Please look at example https://github.com/Zuzon/garmin-parser/tree/master/examples

How to run an example

download repository and run this command

npm install
npm install usb
npm run example

For windows users

delete official garmin driver
associate device to generic WinUsb driver by using Zadig or winusb-driver-generator https://www.npmjs.com/package/winusb-driver-generator (personally i'm using a driver generator in my app, so user can instantly connect to garmin without any extra actions)

API

import { GarminParser } from 'garmin-parser'
...
const garmin = new GarminParser()
...

Methods

garmin.startSession(): Promise

returns device unit ID

const deviceUnitId = await garmin.startSession();

starts session command to activate Application Layer Protocol. Must be called before all another commands

garmin.requestProductData(): Promise

returns ProductData object and configures supported protocols of device, highly recommended to call after start session

garmin.startPvt(): Promise

start PVT translation

garmin.on('pvtData', (data: PVTdataType) => {
    ...
});
garmin.startPvt();

garmin.stopPvt(): Promise

stop PVT data translation

Events

pvtData: Event

event starts coming approx 1 time per second after .startPvt()

{
    raw: {                  // raw object as PVT data type
        alt: number;        // altitude above WGS 84 ellipsoid (meters)
        epe: number;        // estimated position error, 2 sigma (meters)
        eph: number;        // epe, but horizontal only (meters)
        eve: number;        // epe, but vertical only (meters)
        fix: number;        // type of position fix
        tow: number;        // time of week (seconds)
        posn: {
            lat: number;    // latitude in radians
            lon: number;    // longitude in radians
        };
        east: number;       // velocity east (meters/second)
        north: number;      // velocity north (meters/second)
        up: number;         // velocity up (meters/second)
        msl_hght: number;   // height of WGS84 ellipsoid above MSL(meters)
        leap_scnds: number; // difference between GPS and UTC (seconds)
        wn_days: number;    // week number days
    };
    parsed: {               // more javascript and human friendly data
        lat: number;        // latitutde in degrees
        lon: number;        // longitude in degrees
        altitude: number;   // altitude in meters
        dateUTC: Date;      // GPS datetime in UTC
        speedKmh: number;   // speed km/h
        fix: string;        // GPS fix type
    }
}