OpenBCI WiFi Shield NodeJS SDK

Welcome!

First and foremost, Welcome! :tada: Willkommen! :confetti_ball: Bienvenue! :balloon::balloon::balloon:

Thank you for visiting the OpenBCI WiFi Shield NodeJS SDK repository.

This document (the README file) is a hub to give you some information about the project. Jump straight to one of the sections below, or just scroll down to find out more.

• What are we doing? (And why?)
• Who are we?
• What do we need?
• How can you get involved?
• Get in touch
• Find out more
• Understand the jargon

What are we doing?

The problem

• Users continuously struggle to get prerequisites properly installed to get current OpenBCI Cyton and Ganglion, hours/days/weeks are wasted just trying to get the data.
• Bluetooth requires you to stay close to your computer, if you go to far, data is lost and the experiment is over.
• Bluetooth is too slow for transmitting research grade EEG, researchers want 1000Hz (samples per second), bluetooth with 8 channels is limted to 250Hz and with 16 channels limited to 125Hz.
• Bluetooth is unreliable when many other Bluetooth devices are around, demo device or use in busy real life experiment is not reliable. (think grand central station at rush hour)
• Bluetooth requires data to be sent to desktops in raw or compressed form, must use other node modules to parse complex byte streams, prevents from running in browser.
• OpenBCI Cyton (8 and 16 channel) with Bluetooth cannot go to any mobile device because of required Bluetooth-to-USB "Dongle". Must use USB port on Desktop/Laptop computers.
• Bluetooth on Ganglion requires low level drivers to use computers bluetooth hardware.
• The OpenBCI Cyton and Ganglion must transmit data to another computer over Bluetooth before going to the cloud for storage or analytics
• OpenBCI Cyton Dongle FTDI virtual comm port drivers have high latency by default which limits the rate at which new data is made available to your application to twice a second when it should get data as close to 250 times a second.
• Using Cyton or Ganglion NodeJS drivers requires the use of native C++ modules which continuously confuse developers of all levels.

So, if even the very best developers integrate the current easy to use Cyton and Ganglion NodeJS drivers, they are still burdened by the limitations of the physical hardware on the OpenBCI system.

The solution

The OpenBCI WiFi Shield NodeJS SDK will:

• Find, connect, sync, and configure (e.g. set sample rate) with OpenBCI WiFi Shield and Carrier board (Ganglion or Cyton or Cyton with Daisy) in a single function call
• Use TCP over WiFi to prevent packet loss
• Relies on zero native C++ modules
• Enable streaming of high speed (samples rates over 100Hz), low latency (by default, send data every 10ms), research grade EEG (no lost data) directly to any internet connected device (i.e. iPhone, Android, macOS, Windows, Linux, Raspberry Pi 3)
• With WiFi Shield you can now use OpenBCI Ganglion and Cyton anywhere you have a good enough WiFi signal.
• Hotspots create a stable wireless transmission system even in crowded areas

Using WiFi physically solves limitations with the current state-of-the-art open source bio sensor. The goal for the WiFi Shield firmware was to create a one up data pipeline, where scientific data in JSON is sent instead of raw/compressed ADC counts (yuk!) to make programming with OpenBCI reliable, easy, research grade and fun!

Who are we?

The founder of the OpenBCI WiFi Shield NodeJS SDK is AJ Keller.

AJ is an invited member of the 4th cohort Open Leaders Cohort of the Mozilla Science Lab who brought together open science advocates from around the world to participate in the first Working Open Workshop in Berlin in February 2016. The training exercises (which are free and easy to reuse) focused on how to build and effectively engage communities so they can work together to develop tools and resources for the greater good.

What do we need?

You! In whatever way you can help.

We need expertise in programming, user experience, software sustainability, documentation and technical writing and project management.

We'd love your feedback along the way.

Our primary goal is to make programming with OpenBCI reliable, easy, research grade and fun, and we're excited to support the professional development of any and all of our contributors. If you're looking to learn to code, try out working collaboratively, or translate you skills to the digital domain, we're here to help.

Get involved

If you think you can help in any of the areas listed above (and we bet you can) or in any of the many areas that we haven't yet thought of (and here we're sure you can) then please check out our contributors' guidelines and our roadmap.

Please note that it's very important to us that we maintain a positive and supportive environment for everyone who wants to participate. When you join us we ask that you follow our code of conduct in all interactions both on and offline.

Contact us

If you want to report a problem or suggest an enhancement we'd love for you to open an issue at this github repository because then we can get right on it. But you can also contact AJ by email (pushtheworldllc AT gmail DOT com) or on twitter.

You can also hang out, ask questions and share stories in the OpenBCI NodeJS room on Gitter.

Find out more

You might be interested in:

• Purchase a WiFi Shield from OpenBCI
• A NodeJS example for WiFi Shield: getStreaming.js

And of course, you'll want to know our:

• Contributors' guidelines
• Roadmap

Thank you

Thank you so much (Danke schön! Merci beaucoup!) for visiting the project and we do hope that you'll join us on this amazing journey to make programming with OpenBCI fun and easy.

Documentation

Table of Contents:

1. Installation
2. TL;DR
3. Developing
4. Contribute
5. License
6. General Overview
7. Classes
8. Typedefs
9. Wifi

Installation:

We assume you have NodeJS installed already, if you don't please download the latest stable version from NodeJS.

Then simply using the node package manager command line tool, enter:

npm install @openbci/wifi

TL;DR:

Get connected and start streaming right now with the example code.

const Wifi = require('@openbci/wifi');
let wifi = new Wifi({
  debug: false,
  verbose: true,
  latency: 10000
});

wifi.on(k.OBCIEmitterSample, (sample) => {
  for (let i = 0; i < wifi.getNumberOfChannels(); i++) {
    console.log("Channel " + (i + 1) + ": " + sample.channelData[i].toFixed(8) + " Volts.");
     // prints to the console
     //  "Channel 1: 0.00001987 Volts."
     //  "Channel 2: 0.00002255 Volts."
     //  ...
     //  "Channel 8: -0.00001875 Volts."
  }
});

wifi.searchToStream({
    sampleRate: 1000 // Custom sample rate
    shieldName: 'OpenBCI-2C34', // Enter the unique name for your wifi shield
    streamStart: true // Call to start streaming in this function
  }).catch(console.log);

Developing:

Running:

npm install

Testing:

npm test

Contribute:

1. Checkout contributors' guidelines
2. Fork it!
3. Branch off of development: git checkout development
4. Create your feature branch: git checkout -b my-new-feature
5. Make changes
6. If adding a feature, please add test coverage.
7. Ensure tests all pass. (npm test)
8. Commit your changes: git commit -m 'Add some feature'
9. Push to the branch: git push origin my-new-feature
10. Submit a pull request. Make sure it is based off of the development branch when submitting! :D

License:

MIT

General Overview

Initialization

Initializing the board:

const Wifi = require('../../openBCIWifi');
const ourBoard = new Wifi();

Go checkout out the get streaming example!

For initializing with options, such as verbose print outs:

const Wifi = require('../../openBCIWifi');
const wifi = new Wifi({
  verbose: true
});

or if you are using ES6:

import Wifi from '../../openBCIWifi';
import { constants } from '@openbci/utilities';
const wifi = new Wifi();
wifi.connect("OpenBCI-2114");

To debug, it's amazing, do:

const Wifi = require('../../openBCIWifi');
const wifi = new Wifi({
    debug: true
});

Sample properties:

• startByte (Number should be 0xA0)
• sampleNumber (a Number between 0-255)
• channelData (channel data indexed at 0 filled with floating point Numbers in Volts) if sendCounts is false
• channelDataCounts (channel data indexed at 0 filled with floating point Numbers in Volts) if sendCounts is true
• accelData (Array with X, Y, Z accelerometer values when new data available) if sendCounts is false
• accelDataCounts (Array with X, Y, Z accelerometer values when new data available) Only present if sendCounts is true
• auxData (Buffer filled with either 2 bytes (if time synced) or 6 bytes (not time synced))
• stopByte (Number should be 0xCx where x is 0-15 in hex)
• boardTime (Number the raw board time)
• timeStamp (Number the boardTime plus the NTP calculated offset)

The power of this module is in using the sample emitter, to be provided with samples to do with as you wish.

To get a 'sample' event, you need to:

1. Install the 'sample' event emitter
2. Call .searchToStream(_options_)

const Wifi = require('../../openBCIWifi');
let wifi = new Wifi({
  debug: false,
  verbose: true,
  latency: 10000
});

wifi.on(k.OBCIEmitterSample, (sample) => {
  for (let i = 0; i < wifi.getNumberOfChannels(); i++) {
    console.log("Channel " + (i + 1) + ": " + sample.channelData[i].toFixed(8) + " Volts.");
     // prints to the console
     //  "Channel 1: 0.00001987 Volts."
     //  "Channel 2: 0.00002255 Volts."
     //  ...
     //  "Channel 8: -0.00001875 Volts."
  }
});

wifi.searchToStream({
    sampleRate: 1000 // Custom sample rate
    shieldName: 'OpenBCI-2C34', // Enter the unique name for your wifi shield
    streamStart: true // Call to start streaming in this function
  }).catch(console.log);

Close the connection with .streamStop() and disconnect with .disconnect()

const Wifi = require('../../openBCIWifi');
const wifi = new Wifi();
wifi.streamStop().then(wifi.disconnect());

Classes

Typedefs

Wifi

Kind: global class Author: AJ Keller (@aj-ptw)

• Wifi
  • new Wifi(options)
  • instance
    • .options : InitializationObject
    • ._accelArray
    • .curOutputMode
    • .bufferRawDataPackets(rawDataPackets) ⇒ Array
    • .channelOff(channelNumber) ⇒ Promise.<T>
    • .channelOn(channelNumber) ⇒ Promise.<T> | *
    • .channelSet(channelNumber, powerDown, gain, inputType, bias, srb2, srb1) ⇒ Promise
    • .impedanceSet(channelNumber, pInputApplied, nInputApplied) ⇒ Promise
    • .connect(o) ⇒ Promise
    • .disconnect() ⇒ Promise
    • .isConnected() ⇒ boolean
    • .isSearching() ⇒ boolean
    • .isStreaming() ⇒ boolean
    • .getBoardType() ⇒ *
    • .getFirmwareVersion() ⇒ String
    • .getIpAddress() ⇒ null | String
    • .getLatency() ⇒ Number
    • .getMacAddress() ⇒ null | String
    • .getNumberOfChannels() ⇒ Number
    • .getSampleRate() ⇒ Number
    • .getShieldName() ⇒ null | String
    • .impedanceStart() ⇒ global.Promise | Promise
    • .impedanceStop() ⇒ global.Promise | Promise
    • .searchToStream(o) ⇒ Promise
    • .setSampleRate(sampleRate) ⇒ Promise
    • .syncSampleRate() ⇒ Promise
    • .searchStart() ⇒ Promise
    • .searchStop() ⇒ global.Promise | Promise
    • .sdStop() ⇒ Promise
    • .syncRegisterSettings() ⇒ Promise.<T> | *
    • .softReset() ⇒ Promise
    • .eraseWifiCredentials() ⇒ Promise
    • .streamStart() ⇒ Promise
    • .streamStop() ⇒ Promise
    • .syncInfo(o) ⇒ Promise.<TResult>
    • .write(data) ⇒ Promise
    • .destroy()
    • .wifiGetLocalPort() ⇒ number
    • .wifiGetLocalPortUDP() ⇒ number
    • .wifiGetLocalPortTCP() ⇒ number
    • .wifiInitServer()
    • .delete(path) ⇒ Promise
    • .get(path) ⇒ Promise
    • .post(path, payload) ⇒ Promise
  • inner
    • ~o

new Wifi(options)

The initialization method to call first, before any other method.

| Param | Type | Description | | --- | --- | --- | | options | InitializationObject | (optional) - Board optional configurations. |

wifi.options : InitializationObject

Kind: instance property of Wifi

wifi._accelArray

Private Properties (keep alphabetical)

Kind: instance property of Wifi

wifi.curOutputMode

Public Properties (keep alphabetical)

Kind: instance property of Wifi

wifi.bufferRawDataPackets(rawDataPackets) ⇒ Array

This function is for redundancy after a long packet send, the wifi firmware can resend the same packet again, using this till add redundancy on poor networks.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

| Param | Description | | --- | --- | | rawDataPackets | - |

wifi.channelOff(channelNumber) ⇒ Promise.<T>

Send a command to the board to turn a specified channel off

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

| Param | | --- | | channelNumber |

wifi.channelOn(channelNumber) ⇒ Promise.<T> | *

Send a command to the board to turn a specified channel on

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

| Param | | --- | | channelNumber |

wifi.channelSet(channelNumber, powerDown, gain, inputType, bias, srb2, srb1) ⇒ Promise

To send a channel setting command to the board

Kind: instance method of Wifi Returns: Promise - resolves if sent, rejects on bad input or no board Author: AJ Keller (@aj-ptw)

| Param | Description | | --- | --- | | channelNumber | Number (1-16) | | powerDown | Bool (true -> OFF, false -> ON (default)) turns the channel on or off | | gain | Number (1,2,4,6,8,12,24(default)) sets the gain for the channel | | inputType | String (normal,shorted,biasMethod,mvdd,temp,testsig,biasDrp,biasDrn) selects the ADC channel input source | | bias | Bool (true -> Include in bias (default), false -> remove from bias) selects to include the channel input in bias generation | | srb2 | Bool (true -> Connect this input to SRB2 (default), false -> Disconnect this input from SRB2) Select to connect (true) this channel's P input to the SRB2 pin. This closes a switch between P input and SRB2 for the given channel, and allows the P input to also remain connected to the ADC. | | srb1 | Bool (true -> connect all N inputs to SRB1, false -> Disconnect all N inputs from SRB1 (default)) Select to connect (true) all channels' N inputs to SRB1. This effects all pins, and disconnects all N inputs from the ADC. |

wifi.impedanceSet(channelNumber, pInputApplied, nInputApplied) ⇒ Promise

To send an impedance setting command to the board

Kind: instance method of Wifi Returns: Promise - resolves if sent, rejects on bad input or no board Author: AJ Keller (@aj-ptw)

| Param | Type | Description | | --- | --- | --- | | channelNumber | Number | (1-16) | | pInputApplied | Boolean | (true -> ON, false -> OFF (default)) | | nInputApplied | Boolean | (true -> ON, false -> OFF (default)) |

wifi.connect(o) ⇒ Promise

The essential precursor method to be called initially to establish a ble connection to the OpenBCI ganglion board.

Kind: instance method of Wifi Returns: Promise - If the board was able to connect. Author: AJ Keller (@aj-ptw)

| Param | Type | Description | | --- | --- | --- | | o | Object | | | o.burst | Boolean | Set this option true to have UDP do burst mode 3x | | o.examineMode | Boolean | Set this option true to connect to the WiFi Shield even if there is no board attached. | | o.ipAddress | String | The ip address of the shield if you know it | | o.latency | Number | If you want to set the latency of the system you can here too. | | o.protocol | String | Either send the data over TCP or UDP. UDP seems better for either a bad router or slow router. Default is TCP | | o.sampleRate | | The sample rate to set the board connected to the wifi shield | | o.shieldName | String | If supplied, will search for a shield by this name, if not supplied, will connect to the first shield found. | | o.streamStart | Boolean | Set true if you want the board to start streaming. |

wifi.disconnect() ⇒ Promise

Closes the connection to the board. Waits for stop streaming command to be sent if currently streaming.

Kind: instance method of Wifi Returns: Promise - - fulfilled by a successful close, rejected otherwise. Author: AJ Keller (@aj-ptw)

wifi.isConnected() ⇒ boolean

Checks if the driver is connected to a board.

Kind: instance method of Wifi Returns: boolean - - True if connected. Author: AJ Keller (@aj-ptw)

wifi.isSearching() ⇒ boolean

Checks if noble is currently scanning.

Kind: instance method of Wifi Returns: boolean - - True if streaming. Author: AJ Keller (@aj-ptw)

wifi.isStreaming() ⇒ boolean

Checks if the board is currently sending samples.

Kind: instance method of Wifi Returns: boolean - - True if streaming. Author: AJ Keller (@aj-ptw)

wifi.getBoardType() ⇒ *

Get the current board type

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.getFirmwareVersion() ⇒ String

Get the firmware version of connected and synced wifi shield.

Kind: instance method of Wifi Returns: String - The version number Note: This is dependent on if you called connect Author: AJ Keller (@aj-ptw)

wifi.getIpAddress() ⇒ null | String

Return the ip address of the attached WiFi Shield device.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.getLatency() ⇒ Number

Return the latency to be set on the WiFi Shield.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.getMacAddress() ⇒ null | String

Return the MAC address of the attached WiFi Shield device.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.getNumberOfChannels() ⇒ Number

This function is used as a convenience method to determine how many channels the current board is using. Note: This is dependent on if your wifi shield is attached to another board and how many channels are there.

Kind: instance method of Wifi Returns: Number - A number Author: AJ Keller (@aj-ptw)

wifi.getSampleRate() ⇒ Number

Get the the current sample rate is. Note: This is dependent on if you configured the board correctly on setup options

Kind: instance method of Wifi Returns: Number - The sample rate Author: AJ Keller (@aj-ptw)

wifi.getShieldName() ⇒ null | String

Return the shield name of the attached WiFi Shield device.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.impedanceStart() ⇒ global.Promise | Promise

Call to start testing impedance.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.impedanceStop() ⇒ global.Promise | Promise

Call to stop testing impedance.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.searchToStream(o) ⇒ Promise

Used to search for an OpenBCI WiFi Shield. Will connect to the first one if no shieldName is supplied.

Kind: instance method of Wifi Returns: Promise - - Resolves after successful connection, rejects otherwise with Error. Author: AJ Keller (@aj-ptw)

| Param | Type | Description | | --- | --- | --- | | o | Object | (optional) | | o.sampleRate | | The sample rate to set the board connected to the wifi shield | | o.shieldName | String | If supplied, will search for a shield by this name, if not supplied, will connect to the first shield found. | | o.streamStart | Boolean | Set true if you want the board to start streaming. | | o.timeout | Number | The time in milli seconds to wait for the system to try and auto find and connect to the shield. |

wifi.setSampleRate(sampleRate) ⇒ Promise

Set the sample rate of the remote OpenBCI shield

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

| Param | Type | Description | | --- | --- | --- | | sampleRate | Number | the sample rate you want to set to. |

wifi.syncSampleRate() ⇒ Promise

Returns the sample rate from the board

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.searchStart() ⇒ Promise

List available peripherals so the user can choose a device when not automatically found.

Kind: instance method of Wifi Returns: Promise - - If scan was started Author: AJ Keller (@aj-ptw)

wifi.searchStop() ⇒ global.Promise | Promise

Called to end a search.

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

wifi.sdStop() ⇒ Promise

Sends the stop SD logging command to the board. If not streaming then eot event will be emitted with request response from the board.

Kind: instance method of Wifi Returns: Promise - - Resolves when written Author: AJ Keller (@aj-ptw)

wifi.syncRegisterSettings() ⇒ Promise.<T> | *

Syncs the internal channel settings object with a cyton, this will take about over a second because there are delays between the register reads in the firmware.

Kind: instance method of Wifi Returns: Promise.<T> | * - Resolved once synced, rejects on error or 2 second timeout Author: AJ Keller (@aj-ptw)

wifi.softReset() ⇒ Promise

Sends a soft reset command to the board

Kind: instance method of Wifi Returns: Promise - - Fulfilled if the command was sent to board. Author: AJ Keller (@aj-ptw)

wifi.eraseWifiCredentials() ⇒ Promise

Tells the WiFi Shield to forget it's network credentials. This will cause the board to drop all connections.

Kind: instance method of Wifi Returns: Promise - Resolves when WiFi Shield has been reset and the module disconnects. Author: AJ Keller (@aj-ptw)

wifi.streamStart() ⇒ Promise

Sends a start streaming command to the board.

Kind: instance method of Wifi Returns: Promise - indicating if the signal was able to be sent. Note: You must have successfully connected to an OpenBCI board using the connect method. Just because the signal was able to be sent to the board, does not mean the board will start streaming. Author: AJ Keller (@aj-ptw)

wifi.streamStop() ⇒ Promise

Sends a stop streaming command to the board.

Kind: instance method of Wifi Returns: Promise - indicating if the signal was able to be sent. Note: You must have successfully connected to an OpenBCI board using the connect method. Just because the signal was able to be sent to the board, does not mean the board stopped streaming. Author: AJ Keller (@aj-ptw)

wifi.syncInfo(o) ⇒ Promise.<TResult>

Sync the info of this wifi module

Kind: instance method of Wifi Author: AJ Keller (@aj-ptw)

| Param | Type | Description | | --- | --- | --- | | o | Object | | | o.examineMode | Boolean | Set this option true to connect to the WiFi Shield even if there is no board attached. |

wifi.write(data) ⇒ Promise

Used to send data to the board.

Kind: instance method of Wifi Returns: Promise - - fulfilled if command was able to be sent Author: AJ Keller (@aj-ptw)

| Param | Type | Description | | --- | --- | --- | | data | Array | Buffer | Number | String | The data to write out |

wifi.destroy()

Call this to shut down the servers.

Kind: instance method of Wifi

wifi.wifiGetLocalPort() ⇒ number

Get the local port number of either the TCP or UDP server. Based on options.protocol being set to either udp or tcp.

Kind: instance method of Wifi Returns: number - The port number that was dynamically assigned to this module on startup.

wifi.wifiGetLocalPortUDP() ⇒ number

Get the local port number of the UDP server.

Kind: instance method of Wifi Returns: number - The port number that was dynamically assigned to this module on startup.

wifi.wifiGetLocalPortTCP() ⇒ number

Get the local port number of the UDP server.

Kind: instance method of Wifi Returns: number - The port number that was dynamically assigned to this module on startup.

wifi.wifiInitServer()

Initialization function that will start the TCP server and bind the UDP port.

Kind: instance method of Wifi

wifi.delete(path) ⇒ Promise

Send a delete message to the connected wifi shield.

Kind: instance method of Wifi Returns: Promise - - Resolves if gets a response from the client/server, rejects with error

| Param | Type | Description | | --- | --- | --- | | path | String | the path/route to send the delete message to |

wifi.get(path) ⇒ Promise

Send a GET message to the connected wifi shield.

Kind: instance method of Wifi Returns: Promise - - Resolves if gets/with a response from the client/server, rejects with error

| Param | Type | Description | | --- | --- | --- | | path | String | the path/route to send the GET message to |

wifi.post(path, payload) ⇒ Promise

Send a POST message to the connected wifi shield.

Kind: instance method of Wifi Returns: Promise - - Resolves if gets a response from the client/server, rejects with error

| Param | Type | Description | | --- | --- | --- | | path | String | the path/route to send the POST message to | | payload | * | can really be anything but should be a JSON object. |

Wifi~o

Configuring Options

Kind: inner property of Wifi

InitializationObject : Object

Kind: global typedef Properties

| Name | Type | Description | | --- | --- | --- | | attempts | Number | The number of times to try and perform an SSDP search before quitting. (Default 10) | | burst | Boolean | Only applies for UDP, but the wifi shield will send 3 of the same packets on UDP to increase the chance packets arrive to this module (Default false) | | debug | Boolean | Print out a raw dump of bytes sent and received. (Default false) | | latency | Number | The latency, or amount of time between packet sends, of the WiFi shield. The time is in micro seconds! | | protocol | String | Either send the data over TCP or UDP. UDP seems better for either a bad router or slow router. Default is TCP | | sampleRate | Number | The sample rate to set the board to. (Default is zero) | | sendCounts | Boolean | Send integer raw counts instead of scaled floats. (Default false) | | verbose | Boolean | Print out useful debugging events. (Default false) |