Access HID devices through Node.JS
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README.md

node-hid - Access USB HID devices from node.js

Installation

npm install node-hid

Prerequisites:

  • Node.js v0.8 - v4.x+
  • Mac OS X 10.8, Linux (kernel 2.6+), and Windows XP+
  • libudev-dev, libusb-1.0-0-dev (if Linux, see Compile below)
  • git

node-hid uses node-pre-gyp to store pre-built binary bundles, so usually no compiler is needed to install.

Platforms we pre-build binaries for:

  • Mac OS X x64: v0.10, v0.12, v4.2.x
  • Windows x64 & x86: v0.10, v0.12, v4.2.x
  • Linux Debian/Ubuntu x64: v4.2.x
  • Raspberry Pi arm: v4.2.x

If node-hid doesn't have a pre-built binary for your system, it will attempt to compile locally. In which case you'll need the Compiler tools mentioned below.

Test it

In the src/ directory, various JavaScript programs can be found that talk to specific devices in some way. Some interesting ones:

To try them out, call them like node src/showdevices.js from the node-hid directory.

How to Use

Load the module

var HID = require('node-hid');

Get a list of all HID devices in the system:

var devices = HID.devices()

devices will contain an array of objects, one for each HID device available. Of particular interest are the vendorId and productId, as they uniquely identify a device, and the path, which is needed to open a particular device.

Here is some sample output:

HID.devices();
[ { vendorId: 1452,
    productId: 595,
    path: 'USB_05ac_0253_0x100a148e0',
    serialNumber: '',
    manufacturer: 'Apple Inc.',
    product: 'Apple Internal Keyboard / Trackpad',
    release: 280,
    interface: -1 },
  { vendorId: 1452,
    productId: 595,
    path: 'USB_05ac_0253_0x100a14e20',
    serialNumber: '',
    manufacturer: 'Apple Inc.',
    product: 'Apple Internal Keyboard / Trackpad',
    release: 280,
    interface: -1 },
<and more>

NOTE: Most keyboard & mice-like HID devices cannot be seen by node-hid on Windows & Mac. This is not a limitation of node-hid but a limitation of all user-space libraries. This is a security feature of the OS to prevent input device snooping.

Opening a device

Before a device can be read from or written to, it must be opened. The path can be determined by a prior HID.devices() call. Use either the path from the list returned by a prior call to HID.devices():

var device = new HID.HID(path);

or open the first device matching a VID/PID pair:

var device = new HID.HID(vid,pid);

device will contain a handle to the device. If an error occurs opening the device, an exception will be thrown.

Reading from a device

Reading from a device is performed by registering a "data" event handler:

device.on("data", function(data) {});

You can also listen for errors like this:

device.on("error", function(err) {});

All reading is asynchronous.

Writing to a device

Writing to a device is performed using the write call in a device handle. All writing is synchronous.

device.write([0x00, 0x01, 0x01, 0x05, 0xff, 0xff]);

Notes:

  • The write() method sends OUTPUT reports. To send Feature reports, see the sendFeatureReport() method below.
  • Some devices use reportIds for OUTPUT reports. If that is the case, the first byte of the array to write() should be the reportId.

Complete API

var device = new HID.HID(path);

Event: "data"

  • chunk - Buffer - the data read from the device

Event: "error"

  • error - The error Object emitted

device.write(data)

  • data - the data to be synchronously written to the device

device.close()

Closes the device. Subsequent reads will raise an error.

device.pause()

Pauses reading and the emission of data events.

device.resume()

This method will cause the HID device to resume emmitting data events. If no listeners are registered for the data event, data will be lost.

When a data event is registered for this HID device, this method will be automatically called.

device.read(callback)

Low-level function call to initiate an asynchronous read from the device. callback is of the form callback(err, data)

device.readSync()

Return an array of numbers data. If an error occurs, an exception will be thrown.

device.readTimeout(time_out)

  • time_out - timeout in milliseconds Return an array of numbers data. If an error occurs, an exception will be thrown.

device.sendFeatureReport(data)

  • data - data of HID feature report, with 0th byte being report_id ([report_id,...])

device.getFeatureReport(report_id, report_length)

  • report_id - HID feature report id to get
  • report_length - length of report

Notes for Specific Devices

  • Xbox 360 Controller on Windows 10 -- does not work

Compiling from source

To compile & develop locally (or if node-pre-gyp cannot find a pre-built binary for you), you will need the following tools:

  • Mac OS X 10.8+
  • Windows XP+
  • Linux (kernel 2.6+)
    • Compiler tools (apt-get install build-essential git for Debian/Ubuntu/Raspian)
    • libudev-dev (Fedora: yum install libusbx-devel)
    • libusb-1.0-0-dev (Ubuntu versions missing libusb.h only)
    • gcc-4.8+ (apt-get install gcc-4.8 g++-4.8 && export CXX=g++-4.8)

To build node-hid, check out a copy of this repo, change into its directory, update the submodules, build the node package, then node-pre-gyp to rebuild the C code:

git clone https://github.com/node-hid/node-hid.git
cd node-hid                                        # must change into node-hid directory
git submodule update --init                        # done on publish automatically
npm install                                        # rebuilds the module
./node_modules/.bin/node-pre-gyp rebuild           # rebuilds the C code

On Windows CMD shell, the last line will instead need to be:

.\node_modules\.bin\node-pre-gyp rebuild           # rebuilds the C code

You will likely see some warnings from the C compiler as it compiles hidapi. This is expected.

Using node-hid in Electron projects

In your electron project, add electron-rebuild and electron-prebuilt to your devDependencies. Then in your package.json scripts add:

  "postinstall": "electron-rebuild --pre-gyp-fix --force"

If you want a specific version of electron, do something like:

electron-rebuild -v 0.36.5 --pre-gyp-fix --force -m . -w node-hid

Using node-hid in NW.js projects

    npm install node-pre-gyp
    ./node_modules/.bin/node-pre-gyp rebuild --runtime=node-webkit --target=0.12.3

You can change 0.12.3 to version nwjs that you want to deploy.

Support

Please use the node-hid github issues page for support questions and issues.