UBX Parser

A parser for the GNSS protocol ubx. Developed and tested with a ublox M9L GPS module.

``
npm install @nextlvlup/ubx-parser
`

This library was created based on the documentation provided by ublox.
Interface Description
Integration Manual

$3

`ts
import { UBXParser } from "@nextlvlup/ubx-parser";

// Create Parser Instance
const parser = new UBXParser();

// Add Event Listener
parser.on("warning", (warning, buffer) => console.warn(warning));
parser.on("error", (error, buffer) => console.error(error));
parser.on("data", (data, buffer) => console.log(data));
`

the buffer object contains the raw data packet.

$3

If you want to provide the GNSS data from a local Linux device via TCP you can do this with the following command. socat -d -d tcp-l:1234 file://dev/ttyS0,b460800,raw

This command starts a TCP server and serves as a gateway between the local serial port ttyS0 and the TCP client.

`ts
import { Socket } from "net";
import { UBXParser } from "@nextlvlup/ubx-parser";

const client = new Socket();
const parser = new UBXParser();

client.connect({ host: "localhost", port: 1234 }, () => console.log("connected"));

// Pass data to the parser
client.on("data", (buffer) => parser.parse(buffer));
// Receiving parsed data
parser.on("data", (data) => console.log(data));
`

$3

`ts
import { SerialPort } from "serialport";
import { UBXParser } from "@nextlvlup/ubx-parser";

const serialport = new SerialPort({ path: "/dev/ttyS0", baudRate: 460800 }, () => console.log("gps connected"));
const parser = new UBXParser();

// Pass data to the parser
port.on("data", (buffer) => parser.parse(buffer));
// Receiving parsed data
parser.on("data", (data) => console.log(data));
`

$3

The object returned in the data listener always contains a packet_class and a packet_id. These are used to identify what kind of packet it is. The remaining fields are packet-type dependent.

| Field | Type | Example |
| ------------ | ----- | ------- |
| packet_class | uint8 | 0x01 |
| packet_id | uint8 | 0x07 |
| ... | ... | ... |

$3

You can also create your own packet parser if you need a packet that is not yet supported by this library.

`ts
import { UBXParser, readBitFromUInt8, readBitFromUInt16, readBitFromUInt32 } from "@nextlvlup/ubx-parser";

export class CustomParser extends PacketParser {
constructor() {
// pass packet_class and packet_id for identification
super(0x01, 0x07);
}

parse(payload: Buffer): CustomData {
return {
// read uint32 starting at byte 0
iTOW: payload.readUInt32LE(0),
// read uint16 starting at byte 4
year: payload.readUInt16LE(4),
// read uint8 starting at byte 6
month: payload.readUInt8(6),
// read bit 0 from uint8 byte 7
validDate: readBitFromUInt8(payload.readUInt8(7), 0),
// read bit 0 from uint16 byte 8
invalidLlh: readBitFromUInt16(payload.readUInt16LE(8), 0),
// read bit 24 - 29 from uint32 byte 10
dataType: readBitFromUInt32(payload.readUInt32LE(10), 24, 6),
};
}
}

export interface CustomData {
iTOW: number;
year: number;
month: number;
validDate: number;
invalidLlh: number;
dataType: number;
}
`

Then the CustomParser can be registered in the UBXParser instance.

`ts
import { UBXParser } from "@nextlvlup/ubx-parser";
import { CustomParser } from "path/to/your/CustomParser";

const parser = new UBXParser();
parser.registerParser(new CustomParser());
``