BlueHeron

Hex version API docs

BlueHeron is a new Elixir Bluetooth LE Library that communicates directly with Bluetooth modules via HCI. It is VERY much under construction, and we expect the user API to change completely.

On the plus side, BlueHeron has no dependencies on Linux's bluez stack so if you either can't use bluez, don't want to, or have a simple BLE use case, please join us in building this out! We gather on the Elixir Lang slack in the #nerves-bluetooth channel.

Goals

BlueHeron development was started since SmartRent had a need for a very simple BLE interface on one of its Nerves devices. The existing Elixir BLE library, Harald, didn't have enough functionality and we made so many modifications that it no longer felt like the library followed the spirit of what Harald wanted to be.

Our goals here are to make a one-stop BLE library with support for the following:

  • Scan for and connect to BLE peripheral devices (BlueHeron takes on the central role like a smartphone)
  • GATT client support
  • Work with USB and UART-based Bluetooth modules
  • Support BLE beacons
  • BLE peripheral and GATT server support

The current focus is on filling out the central role. The API is quite unstable at the moment and is intended to look more like high level BLE APIs from other languages. Currently, the raw API is helping us learn and iron out quirks quickly.

If you are interested in adding support for the other roles, please let us know either here or on Slack. While we're very interested in part of this library for work, we're also having fun with BLE and figure that we might as well see if we can hit some Nerves use cases too.

Getting started

See the examples for the time being.

Transports

BlueHeron interacts with Bluetooth modules via transports. Transport implementations are not part of this library since they are hardware-specific. See BlueHeronTransportUART and BlueHeronTransportUSB for examples.

HCI Logging

This project includes a Logger backend to dump PKTLOG format. This is the same format that Android, IOS, btstack, hcidump, and bluez use.

Add the backend to debug all data to/from the HCI transport:

iex> Logger.add_backend(BlueHeron.HCIDump.Logger)
BlueHeron.HCIDump.Logger

This will produce a file /tmp/hcidump.pklg that can be loaded into Wireshark.

NOTE This project configures logger so it is always enabled by default.

The BlueHeron.HCIDump.Logger module implements a superset of Elixir's builtin logger and all non-HCI data is forwarded directly to Elixir's Logger.

iex> require BlueHeron.HCIDump.Logger, as: Logger
BlueHeron.HCIDump.Logger
iex> Logger.debug("sample data")

16:43:46.496 [debug] sample data

iex>

Helpful docs

License

The source code is released under Apache License 2.0.

Check NOTICE and LICENSE files for more information.