📦 parser-slip-encoder

| npm | github |

import { SlipEncoder, SlipDecoder } from '@serialport/parser-slip-encoder'
//or
const { SlipEncoder, SlipDecoder } = require('@serialport/parser-slip-encoder')

This package exports two classes.

SlipEncoder

A transform stream that emits SLIP-encoded data for each incoming packet. Unlike most parsers this one is useful for processing input to the serialport instead of output.

Runs in O(n) time, adding a 0xC0 character at the end of each received packet and escaping characters, according to RFC 1055. Runs in O(n) time.

Constructor Arguments

interface SlipEncoderOptions extends TransformOptions {
  /** Custom start byte */
  START?: number
  /** Custom start escape byte */
  ESC_START?: number
  /** custom escape byte */
  ESC?: number
  /** custom end byte */
  END?: number
  /** custom escape end byte */
  ESC_END?: number
  /** custom escape escape byte */
  ESC_ESC?: number
  /** Adds an END character at the beginning of each packet per the Bluetooth Core Specification 4.0, Volume 4, Part D, Chapter 3 "SLIP Layer" and allowed by RFC 1055 */
  bluetoothQuirk?: boolean
}

// Read lines from a text file, then SLIP-encode each and send them to a serial port
const { SerialPort } = require('serialport')
const { SlipEncoder } = require('@serialport/parser-slip-encoder')
const { ReadlineParser } = require('@serialport/parser-readline')

const fileReader = require('fs').createReadStream('/tmp/some-file.txt')
const port = new SerialPort({ path: '/dev/ROBOT', baudRate: 14400 })
const lineParser = fileReader.pipe(new Readline({ delimiter: '\r\n' }))
const encoder = fileReader.pipe(new SlipEncoder())
encoder.pipe(port)

Slip Decoder

Runs in O(n) time, stripping out slip encoding and emitting decoded data. Optionally custom slip escape and delimiters can be provided.

Constructor Arguments

interface SlipDecoderOptions extends TransformOptions {
  /** Custom start byte */
  START?: number
  /** Custom start escape byte */
  ESC_START?: number
  /** custom escape byte */
  ESC?: number
  /** custom end byte */
  END?: number
  /** custom escape end byte */
  ESC_END?: number
  /** custom escape escape byte */
  ESC_ESC?: number
}

Example

// Receive slip encoded data from a serialport and log decoded data
const { SerialPort } = require('serialport')
const { SlipDecoder } = require('@serialport/parser-slip-encoder')
const port = new SerialPort({ path: '/dev/ROBOT', baudRate: 14400 })
const parser = port.pipe(new SlipDecoder())
parser.on('data', console.log)