Common Bindings for Bluetooth LE

This project aims to abstract out platform-specific differences, and make Bluetooth LE consistent to use across:

• Windows (WinRT)
• Linux (BlueZ)
• macOS
• iOS
• Android

It will eventually provide bindings for, at least:

• C / C++
• Unity
• Python 3

It will achieve this by channeling the platform-specific calls / functionality through a C middleware, compiled into a library. Unity, Python etc will then call the native C functions within the library.

Potential Alternatives

• btleplug might be a more sensible choice, if you need robust Linux support and/or are happy using Rust (or can write suitable bindings). (It's possible that I'll turn this project into Python/Unity bindings for btleplug in the future).
• bleak for Python, if you're able to use asyncio.

Uses

It is intended for:

• Interfacing an application or game with a custom BLE peripheral
• Datalogging
• Automatic testing

It is NOT currently intended to support:

• Multiple BLE adaptors
• Windows versions before 10 (no scanning functionality available in the legacy BLE libraries)
• Any device profiles, even standard ones (Device Information Service, Battery Service etc). Interpreting the received data is up to the app or another library.
• Beacons or advertising
• Classic Bluetooth devices
• Central role
• Connecting to multiple devices simultaneously (assumption of single device is hard-coded in several places)
• Ultra high performance applications (connection process retrives all characteristics of all services)
• Integration into large or complex projects - these may be better suited to integrating Chromium
• Anything safety-critical or high-reliability

Status

This entire project should be considered a work-in-progress with an unstable interface, however the Android, iOS and macOS implementations are well-tested and robust. WinRT is working but largely untested. Linux (BlueZ) is in development and not ready for use.

The bindings are rough examples only, you should use them as a starting point rather than a full reference implementation.

Getting Started

Building

• Android, macOS, iOS: Run the relevant build script within src/.
• Windows: Open src/build-environments/Windows/cobble.sln in Visual Studio and build it.

Binaries are created within src/build.

C/C++

See C header file src/cobble.h.

Unity

An example binding script can be found within bindings/unity. You should build and import the libraries for each platform you intend to support, making sure you configure the architectures / platforms correctly for each library.

Python

An example binding is found within bindings/python.

Platform-specific limitations

• iOS / macOS don't tell you whether a characteristic value has been obtained as a result of a notification or a read.
• macOS Monterey doesn't support scanning unless an advertised service UUID is known - using a blank service filter gives no scan results (rather than all scan results). iOS appears unaffected.