A Node.js module for implementing BLE (Bluetooth Low Energy) peripherals.
Need a BLE central module? See noble.
Note: macOS / Mac OS X, Linux, FreeBSD and Windows are currently the only supported OSes.
Prerequisites
OS X
- install Xcode
- 10.9 or later
Linux
- Kernel version 3.6 or above
libbluetooth-dev
-
bluetoothd
disabled, if BlueZ 5.14 or later is installed. Usesudo hciconfig hci0 up
to power Bluetooth adapter up after stopping or disablingbluetoothd
.-
System V
:-
sudo service bluetooth stop
(once) -
sudo update-rc.d bluetooth remove
(persist on reboot)
-
-
systemd
-
sudo systemctl stop bluetooth
(once) -
sudo systemctl disable bluetooth
(persist on reboot)
-
-
If you’re using noble and bleno at the same time, connected BLE devices may not be able to retrieve a list of services from the BLE adaptor. Check out noble’s documentation on bleno compatibility
Ubuntu/Debian/Raspbian
sudo apt-get install bluetooth bluez libbluetooth-dev libudev-dev
Make sure node
is on your path, if it’s not, some options:
- symlink
nodejs
tonode
: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-devel
Intel Edison
See Configure Intel Edison for Bluetooth LE (Smart) Development
FreeBSD
Make sure you have GNU Make:
sudo pkg install gmake
Disable 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_ubt
Make sure you have read and write permissions on the /dev/usb/*
device that corresponds to your Bluetooth adapter.
Windows
-
node-gyp requirements for Windows
- Python 2.7
- Visual Studio (Express)
-
node-bluetooth-hci-socket prerequisites
- Compatible Bluetooth 4.0 USB adapter
- WinUSB driver setup for Bluetooth 4.0 USB adapter, using Zadig tool
Install
npm install bleno
Usage
var bleno = require('bleno');
See examples folder for code examples.
Actions
Advertising
Start advertising
NOTE: bleno.state
must be poweredOn
before advertising is started. bleno.on('stateChange', callback(state));
can be used register for state change events.
var name = 'name';
var serviceUuids = ['fffffffffffffffffffffffffffffff0']
bleno.startAdvertising(name, serviceUuids[, callback(error)]);
Note:: there are limits on the name and service UUID’s
- name
- maximum 26 bytes
- service UUID’s
- 1 128-bit service UUID
- 1 128-bit service UUID + 2 16-bit service UUID’s
- 7 16-bit service UUID
Start advertising iBeacon
var uuid = 'e2c56db5dffb48d2b060d0f5a71096e0';
var major = 0; // 0x0000 - 0xffff
var minor = 0; // 0x0000 - 0xffff
var measuredPower = -59; // -128 - 127
bleno.startAdvertisingIBeacon(uuid, major, minor, measuredPower[, callback(error)]);
Notes::
- OS X:
- in iBeacon mode your peripheral is non-connectable!
Start advertising with EIR data (Linux only)
var scanData = new Buffer(...); // maximum 31 bytes
var advertisementData = new Buffer(...); // maximum 31 bytes
bleno.startAdvertisingWithEIRData(advertisementData[, scanData, callback(error)]);
- For EIR format section Bluetooth Core Specification sections and 8 and 18 for more information the data format.
Stop advertising
bleno.stopAdvertising([callback]);
Set services
Set the primary services available on the peripheral.
var services = [
... // see PrimaryService for data type
];
bleno.setServices(services[, callback(error)]);
Disconnect client
bleno.disconnect(); // Linux only
Update RSSI
bleno.updateRssi([callback(error, rssi)]); // not available in OS X 10.9
Primary Service
var PrimaryService = bleno.PrimaryService;
var primaryService = new PrimaryService({
uuid: 'fffffffffffffffffffffffffffffff0', // or 'fff0' for 16-bit
characteristics: [
// see Characteristic for data type
]
});
Characteristic
var Characteristic = bleno.Characteristic;
var characteristic = new Characteristic({
uuid: 'fffffffffffffffffffffffffffffff1', // or 'fff1' for 16-bit
properties: [ ... ], // can be a combination of 'read', 'write', 'writeWithoutResponse', 'notify', 'indicate'
secure: [ ... ], // enable security for properties, can be a combination of 'read', 'write', 'writeWithoutResponse', 'notify', 'indicate'
value: null, // optional static value, must be of type Buffer - for read only characteristics
descriptors: [
// see Descriptor for data type
],
onReadRequest: null, // optional read request handler, function(offset, callback) { ... }
onWriteRequest: null, // optional write request handler, function(data, offset, withoutResponse, callback) { ...}
onSubscribe: null, // optional notify/indicate subscribe handler, function(maxValueSize, updateValueCallback) { ...}
onUnsubscribe: null, // optional notify/indicate unsubscribe handler, function() { ...}
onNotify: null, // optional notify sent handler, function() { ...}
onIndicate: null // optional indicate confirmation received handler, function() { ...}
});
Result codes
- Characteristic.RESULT_SUCCESS
- Characteristic.RESULT_INVALID_OFFSET
- Characteristic.RESULT_INVALID_ATTRIBUTE_LENGTH
- Characteristic.RESULT_UNLIKELY_ERROR
Read requests
Can specify read request handler via constructor options or by extending Characteristic and overriding onReadRequest.
Parameters to handler are
-
offset
(0x0000 – 0xffff) callback
callback
must be called with result and data (of type Buffer
) – can be async.
var result = Characteristic.RESULT_SUCCESS;
var data = new Buffer( ... );
callback(result, data);
Write requests
Can specify write request handler via constructor options or by extending Characteristic and overriding onWriteRequest.
Parameters to handler are
-
data
(Buffer) -
offset
(0x0000 – 0xffff) -
withoutResponse
(true | false) -
callback
.
callback
must be called with result code – can be async.
var result = Characteristic.RESULT_SUCCESS;
callback(result);
Notify subscribe
Can specify notify subscribe handler via constructor options or by extending Characteristic and overriding onSubscribe.
Parameters to handler are
-
maxValueSize
(maximum data size) -
updateValueCallback
(callback to call when value has changed)
Notify unsubscribe
Can specify notify unsubscribe handler via constructor options or by extending Characteristic and overriding onUnsubscribe.
Notify value changes
Call the updateValueCallback
callback (see Notify subscribe), with an argument of type Buffer
Can specify notify sent handler via constructor options or by extending Characteristic and overriding onNotify.
Descriptor
var Descriptor = bleno.Descriptor;
var descriptor = new Descriptor({
uuid: '2901',
value: 'value' // static value, must be of type Buffer or string if set
});
Events
Adapter state change
state = <"unknown" | "resetting" | "unsupported" | "unauthorized" | "poweredOff" | "poweredOn">
bleno.on('stateChange', callback(state));
Advertisement started
bleno.on('advertisingStart', callback(error));
bleno.on('advertisingStartError', callback(error));
Advertisement stopped
bleno.on('advertisingStop', callback);
Services set
bleno.on('servicesSet', callback(error));
bleno.on('servicesSetError', callback(error));
Accept
bleno.on('accept', callback(clientAddress)); // not available on OS X 10.9
Disconnect
bleno.on('disconnect', callback(clientAddress)); // Linux only
RSSI Update
bleno.on('rssiUpdate', callback(rssi)); // not available on OS X 10.9
Running on Linux
Note: Make sure you’ve also checked the Linux Prerequisites
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 BLENO_HCI_DEVICE_ID
environment variable to the interface number.
Example, specify hci1
:
sudo BLENO_HCI_DEVICE_ID=1 node .js
Set custom device name
By default bleno uses the hostname (require('os').hostname()
) as the value for the device name (0x2a00) characterisic, to match the behaviour of OS X.
A custom device name can be specified by setting the BLENO_DEVICE_NAME
environment variable:
sudo BLENO_DEVICE_NAME="custom device name" node .js
or
process.env['BLENO_DEVICE_NAME'] = 'custom device name';
Set Advertising Interval
bleno uses a 100 ms advertising interval by default.
A custom advertising interval can be specified by setting the BLENO_ADVERTISING_INTERVAL
enviroment variable with the desired value in milliseconds:
sudo BLENO_ADVERTISING_INTERVAL=500 node .js
Advertising intervals must be between 20 ms to 10 s (10,000 ms).
Useful tools/links
- Tools
- LightBlue for iOS/OS X
- nRF Master Control Panel (BLE) for Android
-
hcitool and
gatttool
by BlueZ for Linux
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