sandeepmistry
A Node.js BLE (Bluetooth Low Energy) central module.
Want to implement a peripheral? Checkout bleno
Note: macOS / Mac OS X, Linux, FreeBSD and Windows are currently the only supported OSes. Other platforms may be developed later on.
Prerequisites
OS X
- install Xcode
Linux
- Kernel version 3.6 or above
libbluetooth-dev
Ubuntu/Debian/Raspbian
sudo apt-get install bluetooth bluez libbluetooth-dev libudev-devMake sure node is on your path, if it's not, some options:
- symlink
nodejstonode:sudo ln -s /usr/bin/nodejs /usr/bin/node - install Node.js using the NodeSource package
Fedora / Other-RPM based
sudo yum install bluez bluez-libs bluez-libs-develIntel Edison
See Configure Intel Edison for Bluetooth LE (Smart) Development
FreeBSD
Make sure you have GNU Make:
sudo pkg install gmakeDisable automatic loading of the default Bluetooth stack by putting no-ubt.conf into /usr/local/etc/devd/no-ubt.conf and restarting devd (sudo service devd restart).
Unload ng_ubt kernel module if already loaded:
sudo kldunload ng_ubtMake sure you have read and write permissions on the /dev/usb/* device that corresponds to your Bluetooth adapter.
Windows
node-gyp requirements for Windows
Install the required tools and configurations using Microsoft's windows-build-tools from an elevated PowerShell or cmd.exe (run as Administrator).
npm install --global --production windows-build-toolsnode-bluetooth-hci-socket prerequisites
- Compatible Bluetooth 4.0 USB adapter
- WinUSB driver setup for Bluetooth 4.0 USB adapter, using Zadig tool
See @don's set up guide on Bluetooth LE with Node.js and Noble on Windows
Notes
Maximum simultaneous connections
This limit is imposed upon by the Bluetooth adapter hardware as well as it's firmware.
| Platform | |
|---|---|
| OS X 10.11 (El Capitan) | 6 |
| Linux/Windows - Adapter dependent | 5 (CSR based adapter) |
Adapter specific known issues
Some BLE adapters cannot connect to a peripheral while they are scanning (examples below). You will get the following messages when trying to connect :
Sena UD-100 (Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode)) : Error: Command disallowed
Intel Dual Band Wireless-AC 7260 (Intel Corporation Wireless 7260 (rev 73)) : Error: Connection Rejected due to Limited Resources (0xd)
You need to stop scanning before trying to connect in order to solve this issue.
Install
npm install nobleUsage
var noble = require('noble');Actions
Start scanning
noble.startScanning(); // any service UUID, no duplicates
noble.startScanning([], true); // any service UUID, allow duplicates
var serviceUUIDs = ["<service UUID 1>", ...]; // default: [] => all
var allowDuplicates = <false|true>; // default: false
noble.startScanning(serviceUUIDs, allowDuplicates[, callback(error)]); // particular UUID'sNOTE: noble.state must be poweredOn before scanning is started. noble.on('stateChange', callback(state)); can be used register for state change events.
Stop scanning
noble.stopScanning();Peripheral
Connect
peripheral.connect([callback(error)]);Disconnect or cancel pending connection
peripheral.disconnect([callback(error)]);Update RSSI
peripheral.updateRssi([callback(error, rssi)]);Discover services
peripheral.discoverServices(); // any service UUID
var serviceUUIDs = ["<service UUID 1>", ...];
peripheral.discoverServices(serviceUUIDs[, callback(error, services)]); // particular UUID'sDiscover all services and characteristics
peripheral.discoverAllServicesAndCharacteristics([callback(error, services, characteristics)]);Discover some services and characteristics
var serviceUUIDs = ["<service UUID 1>", ...];
var characteristicUUIDs = ["<characteristic UUID 1>", ...];
peripheral.discoverSomeServicesAndCharacteristics(serviceUUIDs, characteristicUUIDs, [callback(error, services, characteristics));Service
Discover included services
service.discoverIncludedServices(); // any service UUID
var serviceUUIDs = ["<service UUID 1>", ...];
service.discoverIncludedServices(serviceUUIDs[, callback(error, includedServiceUuids)]); // particular UUID'sDiscover characteristics
service.discoverCharacteristics() // any characteristic UUID
var characteristicUUIDs = ["<characteristic UUID 1>", ...];
service.discoverCharacteristics(characteristicUUIDs[, callback(error, characteristics)]); // particular UUID'sCharacteristic
Read
characteristic.read([callback(error, data)]);Write
characteristic.write(data, withoutResponse[, callback(error)]); // data is a buffer, withoutResponse is true|falsewithoutResponse:false: send a write request, used with "write" characteristic propertytrue: send a write command, used with "write without response" characteristic property
Broadcast
characteristic.broadcast(broadcast[, callback(error)]); // broadcast is true|falseSubscribe
characteristic.subscribe([callback(error)]);- subscribe to a characteristic, triggers
'data'events when peripheral sends an notification or indication - use for characteristics with notify or indicate properties
Unsubscribe
characteristic.unsubscribe([callback(error)]);- unsubscribe to a characteristic
- use for characteristics with notify or indicate properties
Discover descriptors
characteristic.discoverDescriptors([callback(error, descriptors)]);Read value
descriptor.readValue([callback(error, data)]);Write value
descriptor.writeValue(data[, callback(error)]); // data is a bufferHandle
Read
peripheral.readHandle(handle, callback(error, data));Write
peripheral.writeHandle(handle, data, withoutResponse, callback(error));Events
See Node.js EventEmitter docs for more info. on API's.
Adapter state change
state = <"unknown" | "resetting" | "unsupported" | "unauthorized" | "poweredOff" | "poweredOn">
noble.on('stateChange', callback(state));Scan started:
noble.on('scanStart', callback);The event is emitted when scanning is started or if another application enables scanning or changes scanning settings.
Scan stopped
noble.on('scanStop', callback);The event is emitted when scanning is stopped or if another application stops scanning.
Peripheral discovered
peripheral = {
id: "<id>",
address: "<BT address">, // Bluetooth Address of device, or 'unknown' if not known
addressType: "<BT address type>", // Bluetooth Address type (public, random), or 'unknown' if not known
connectable: <connectable>, // true or false, or undefined if not known
advertisement: {
localName: "<name>",
txPowerLevel: <int>,
serviceUuids: ["<service UUID>", ...],
serviceSolicitationUuid: ["<service solicitation UUID>", ...],
manufacturerData: <Buffer>,
serviceData: [
{
uuid: "<service UUID>"
data: <Buffer>
},
...
]
},
rssi: <rssi>
};
noble.on('discover', callback(peripheral));Note: on OS X the address will be set to 'unknown' if the device has not been connected previously.
Warnings
noble.on('warning', callback(message));Peripheral
Connected
peripheral.once('connect', callback);Disconnected:
peripheral.once('disconnect', callback);RSSI update
peripheral.once('rssiUpdate', callback(rssi));Services discovered
peripheral.once('servicesDiscover', callback(services));Service
Included services discovered
service.once('includedServicesDiscover', callback(includedServiceUuids));Characteristics discovered
characteristic = {
uuid: "<uuid>",
// properties: 'broadcast', 'read', 'writeWithoutResponse', 'write', 'notify', 'indicate', 'authenticatedSignedWrites', 'extendedProperties'
properties: [...]
};
service.once('characteristicsDiscover', callback(characteristics));Characteristic
Data
Emitted when characteristic read has completed, result of characteristic.read(...) or characteristic value has been updated by peripheral via notification or indication - after having been enabled with notify(true[, callback(error)]).
characteristic.on('data', callback(data, isNotification));
characteristic.once('read', callback(data, isNotification)); // legacyNote: isNotification event parameter value MAY be undefined depending on platform support. The parameter is deprecated after version 1.8.1, and not supported when on macOS High Sierra and later.
Write
Emitted when characteristic write has completed, result of characteristic.write(...).
characteristic.once('write', withoutResponse, callback());Broadcast
Emitted when characteristic broadcast state changes, result of characteristic.broadcast(...).
characteristic.once('broadcast', callback(state));Notify
Emitted when characteristic notification state changes, result of characteristic.notify(...).
characteristic.once('notify', callback(state));Descriptors discovered
descriptor = {
uuid: '<uuid>'
};
characteristic.once('descriptorsDiscover', callback(descriptors));Descriptor
Value read
descriptor.once('valueRead', data);Value write
descriptor.once('valueWrite');Running on Linux
Running without root/sudo
Run the following command:
sudo setcap cap_net_raw+eip $(eval readlink -f `which node`)This grants the node binary cap_net_raw privileges, so it can start/stop BLE advertising.
Note: The above command requires setcap to be installed, it can be installed using the following:
- apt:
sudo apt-get install libcap2-bin - yum:
su -c \'yum install libcap2-bin\'
Multiple Adapters
hci0 is used by default to override set the NOBLE_HCI_DEVICE_ID environment variable to the interface number.
Example, specify hci1:
sudo NOBLE_HCI_DEVICE_ID=1 node <your file>.jsReporting all HCI events
By default noble waits for both the advertisement data and scan response data for each Bluetooth address. If your device does not use scan response the following environment variable can be used to bypass it.
sudo NOBLE_REPORT_ALL_HCI_EVENTS=1 node <your file>.jsbleno compatibility
By default noble will respond with an error whenever a GATT request message is received. If your intention is to use bleno in tandem with noble, the following environment variable can be used to bypass this functionality. Note: this requires a Bluetooth 4.1 adapter.
sudo NOBLE_MULTI_ROLE=1 node <your file>.jsAdvanced usage
Override default bindings
By default, noble will select bindings to communicate with Bluetooth devices depending on your platform. If you prefer to specify what bindings noble should use:
var noble = require('noble/with-bindings')(require('./my-custom-bindings'));Backers
Support us with a monthly donation and help us continue our activities. [Become a backer]
Sponsors
Become a sponsor and get your logo on our README on Github with a link to your site. [Become a sponsor]
Useful Links
License
Copyright (C) 2015 Sandeep Mistry sandeep.mistry@gmail.com
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.