eChip WebUSB Library

Overview

This development documentation outlines the use of the Keiser eChip as a means of collecting workout information from Keiser Strength and Functional equipment. In order to use the eChip, equipment must have the Power Display with the eChip slot in the bottom right corner. Data that exists on the eChip that pre-dates the current time by at least 2 hours will be displayed on the display as "target" data.

A single eChip is capable of holding 200 workout sets worth of data from 24 distinct machines. If the eChip is full, machines will replace the oldest workout record on the eChip with new data. It is recommended to completely clear the eChip between uses and to only write the data required for targeting during the current workout session.

WebUSB Library

To ease development of software utilizing the eChip, Keiser maintains an Open-Source library that allows web applications to utilize the WebUSB standards to interface with the eChip reader from within a browser. The library is written in TypeScript and available on npm.

Project Home: GitHub.com/KeiserCorp/Keiser.Air.eChip.WebUSB

NPM Package: @keiser/echip-webusb

Requirements

Required Hardware: USB to 1-Wire/iButton Adapter (DS9490)

Required Drivers: 1-Wire/iButton Drivers for Windows

Installation

Install with npm: npm install @keiser/echip-webusb

Usage

Import singleton instance from module using preferred module loading technique.

import ChipReaderWatcher from '@keiser/echip-webusb'

if (ChipReaderWatcher.isConnected) {
  console.log('Chip Reader Connected ๐Ÿ˜„')
}

The ChipReaderWatcher handles permissions and USB connection events. On first load, the browser will not have provided a grant to the site to access the USB device, so the ChipReaderWatcher.start() method must be called by an event that originates from a user action. This may only be required once on the first visit to the site, or it may be required each time the site is loaded based on browser vendors preferred implementation.

connectButton.addEventListener('click', async () => {
  try {
    await ChipReaderWatcher.start()
  } catch (error) {
    console.error(error.message)
  }
})

Once the ChipReaderWatcher.start() method has been called the class will prompt the browser for permission and begin watching for devices matching the Chip Readers device signature. To be alerted when a device is found, pass a function to the ChipReaderWatcher.onConnect() method.

ChipReaderWatcher.onConnect((chipReader) => {
  console.log('Chip Reader Connected ๐Ÿ˜„')
})

The ChipReaderWatcher.onConnect() will pass in a ChipReader object which is the object bound to the physical device connected. This library is capable of handling multiple Chip Reader devices simultaneously, so the onConnect() method has potential for returning multiple ChipReader devices over the course of the application's life.

chipReader.onDisconnect(() => {
  console.log('Chip Reader Disconnected ๐Ÿ˜ž')
})

The ChipReader object has an onDisconnect() method which will alert when the Chip Reader has been disconnected for some reason. Once a ChipReader object has been disconnected, it is disposed and cannot be used again. The next time the device is connected, a new ChipReader object will be returned.

chipReader.onChipDetect(async (chip) => {
  console.log('Chip Connected: ' + chip.id)
  console.log(await chip.getData())
})

The ChipReader object also has an onChipDetect() method which will alert when a valid chip has been placed into the reader. The event passes in a Chip object that can be used to interact with the chip data directly. Just like the ChipReaderWatcher.onConnect() method, the ChipReader.onChipDetect() method can be called multiple times for multiple chips all being handled concurrently. Once a chip is disconnected, the Chip object is disposed and cannot be reused.

Example

import ChipReaderWatcher from '@keiser/echip-webusb'

document.addEventListener('DOMContentLoaded', event => {
  const connectButton = document.querySelector('#connect') as HTMLInputElement

  if (connectButton) {
    connectButton.addEventListener('click', async () => {
      try {
        await ChipReaderWatcher.start()
      } catch (error) {
        console.error(error.message)
      }
    })
  }

  ChipReaderWatcher.onConnect((chipReader) => {
    console.log('Chip Reader Connected ๐Ÿ˜„')

    chipReader.onChipDetect(async (chip) => {
      console.log('Chip Connected: ' + chip.id)
      chip.onData(data => console.log(data))
    })

    chipReader.onDisconnect(() => {
      console.log('Chip Reader Disconnected ๐Ÿ˜ž')
    })
  })
})

API

ChipReaderWatcher

The ChipReaderWatcher is a singleton class which handles the USB device monitoring and permissions handling. There can be only one ChipReaderWatcher instance created within a window scope, so the library instantiates the class during import and preserves a single instance for all imports.

Properties

NameUsage
isConnected: booleanIndicates whether a Chip Reader device is connected

Methods

NameUsage
onConnect(Listener<ChipReader>): DisposableAdds an event listener for when a Chip Reader device is connected. Callback method will be passed the new ChipReader instance for the connected device.
start(): Promise<void>Initializes the watcher by first requesting permissions and then doing a hardware search. This method must be triggered by a user action such as a click event or the permission request will be denied.
stop(): Promise<void>Closes all active connections.

ChipReader

The ChipReader instance is passed into the onConnect callback function and is the interface to the connected Chip Reader device.

Properties

NameUsage
claimed: Promise<boolean>Promise indicating if the USB device interface has been claimed.
disposed: booleanIndicates if the device connection has been severed and the class instance disposed.

Methods

NameUsage
onChipDetect(Listener<Chip>): DisposableAdds an event listener for when a chip is connected to the Chip Reader device. Callback method will be passed the new Chip instance for the connected chip.
onDisconnect(Listener<null>): DisposableAdds an event listener for when this Chip Reader device becomes disconnected. The instance will be disposed following this event.

BaseChip

The BaseChip instance is passed into the onChipDetect callback function and is the interface to the connected chip device. There are several different extensions to the base BaseChip object that can identified by doing a instanceOf check or looking at the type property.

Properties

NameUsage
disposed: booleanIndicates if the eChip connection has been severed and the class instance disposed.
data: ChipObjectGeneric object with the current data from the chip.
id: stringUUID string of the eChip.
type: ChipTypeChipType enum value corresponding to the type of chip.

Methods

NameUsage
destroy(): voidCalled to disconnect the eChip device.
onDisconnect(Listener<null>): DisposableAdds an event listener for when this chip becomes disconnected. The instance will be disposed following this event.
onData(Listener<ChipObject>): DisposableAdds an event listener for when the chip data has changed.

TZChip and RTCChip

The TZChip and RTCChip are class extensions on the BaseChip class. They add no additional properties or methods, but allow the identification of chip type and will perform chip set operations automatically when detected. An event issued on the onData event indicates that the chips data has been successfully updated.

DataChip

The DataChip class extension on the BaseChip class adds additional properties and methods specific to the data chip.

Methods

NameUsage
clearData(): Promise<void>Method clears the data on the chip and resolve the promise on successful write. An onData event will be issues for the blank chip data.
setData({string: MachineObject}): Promise<void>Method sets the data on the chip according to the data passed into the method. The method accepts an object with string keys corresponding to the machine's 4-digit model number with the MachineObject as the value of the property. Method resolve the promise on successful write. An onData event will be issues for the freshly written chip data.

Data Structures

ChipObject

interface ChipObject {
  type: ChipType
}

DataChipObject

interface DataChipObject {
  type: ChipType
  machineData: {[index: string]: MachineObject}
  rawData: Uint8Array[]
  validStructure: boolean
}

MachineObject

interface MachineObject {
  position: MachinePosition
  sets: MachineSet[]
}

MachinePosition

interface MachinePosition {
  chest: number | null
  rom2: number | null
  rom1: number | null
  seat: number | null
}

MachineSet

interface MachineSet {
  version: string
  serial: string
  time: string
  resistance: number
  precision: Precision
  units: ForceUnit
  repetitions: number
  peak: number | null
  work: number | null
  distance: number | null
  chest: number | null
  rom2: number | null
  rom1: number | null
  seat: number | null
  test: MachineTest | null
}

MachineTest

interface MachineTest {
  type: TestType
  high: MachineTestResult | null
  low: MachineTestResult | null
}

MachineTestResult

interface MachineTestResult {
  power: number
  velocity: number
  force: number
  position: number
}

Constants

enum Precision {
  dec = 'dec',
  int = 'int'
 }

enum ForceUnit {
  lb = 'lb',
  kg = 'kg',
  ne = 'ne',
  er = 'er'
}

enum TestType {
  power6r = 'power6r',
  a4206r = 'a4206r',
  a42010r = 'a42010r'
}

enum ChipType {
  dataChip = 12,
  rtcChip = 36,
  tzChip = 45,
  unknown = 0
}

Agreements and Guidelines

Using any of the APIs outlined in document make you subject to the following agreements. Please read all documents in their entirety as they govern your use of the APIs.