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
    }
}