quanteek/bluetoe

C++ Bluetooth LE Server (GATT)

Bluetoe

Overview

Bluetoe implements a GATT server with a very low memory footprint and a convenience C++ interface. Bluetoe makes easy things easy but gives the opportunity to fiddle with all the low level GATT details if necessary. The main target of Bluetoe is to be implemented on very small microcontrollers. Here is an example of a small GATT server:

#include <bluetoe/server.hpp>
#include <bluetoe/service.hpp>
#include <bluetoe/characteristic.hpp>

std::int32_t temperature;
const char serivce_name[]        = "Temperature / Bathroom";
const char characteristic_name[] = "Temperature in 10th degree celsius";

typedef bluetoe::server<
    bluetoe::server_name< server_name >,
    bluetoe::service<
        bluetoe::service_uuid< 0x8C8B4094, 0x0000, 0x499F, 0xA28A, 0x4EED5BC73CA9 >,
        bluetoe::characteristic<
            bluetoe::characteristic_name< char_name >,
            bluetoe::characteristic_uuid< 0x8C8B4094, 0x0000, 0x499F, 0xA28A, 0x4EED5BC73CAA >,
            bluetoe::bind_characteristic_value< decltype( temperature ), &temperature >
        >
    >
> temperature_service;

int main()
{
    temperature_service                                             server;
    bluetoe::binding::btstack_libusb_device< temperature_service >  device;

    device.run( server );
}

Documentation

http://torstenrobitzki.github.io/bluetoe/

L2CAP

Bluetoe ships with its own link layer. Currently a link layer based on the nrf51422 is under construction. The link layer implementation will be based and tested on an abstract device, called a scheduled radio and should be easily ported to similar hardware. As Bluetoe is a GATT server implementation, only that parts of the link layer are implemented, that are nessary. Bluetoe can easily adapted to any other existing L2CAP implementation (based on HCI for example).

Current State

The following table show the list of GATT procedures and there implementation status and there planned implementation status:

Feature	Sub-Procedure	Status
Server Configuration	Exchange MTU	implemented
Primary Service Discovery	Discover All Primary Services	implemented
Discover Primary Service By Service UUID	implemented
Relationship Discovery	Find Included Services	implemented
Characteristic Discovery	Discover All Characteristic of a Service	implemented
Discover Characteristic by UUID	implemented
Characteristic Descriptor Discovery	Discover All Characteristic Descriptors	implemented
Characteristic Value Read	Read Characteristic Value	implemented
Read Using Characteristic UUID	implemented
Read Long Characteristic Value	implemented
Read Multiple Characteristic Values	implemented
Characteristic Value Write	Write Without Response	implemented
Signed Write Without Response	not planned
Write Characteristic Value	implemented
Write Long Characteristic Values	implemented
Characteristic Value Reliable Writes	implemented
Characteristic Value Notification	Notifications	implemented
Characteristic Value Indication	Indications	planned
Characteristic Descriptor Value Read	Read Characteristic Descriptors	implemented
Read Long Characteristic Descriptors	implemented
Characteristic Descriptor Value Write	Write Characteristic Descriptors	implemented
Write Long Characteristic Descriptors	implemented
Cryptography	Encryption	not planned
Authentication	not planned

This is the current state of implemented Advertising Data:

Advertising Data	Format	Status
Service UUID	Incomplete List of 16-bit Service UUIDs	planned
Complete List of 16-bit Service UUIDs	planned
Incomplete List of 32-bit Service UUIDs	planned
Complete List of 32-bit Service UUIDs	planned
Incomplete List of 128-bit Service UUIDs	planned
Complete List of 128-bit Service UUIDs	planned
Local Name	Shortened Local Name	implemented
Complete Local Name	implemented
Flags	Flags	planned
Manufacturer Specific Data	Manufacturer Specific Data	planned
TX Power Level	TX Power Level	planned
Secure Simple Pairing Out of Band		not planned
Security Manager Out of Band		not planned
Security Manager TK Value		not planned
Slave Connection Interval Range		not planned
Service Solicitation		not planned
Service Data		not planned
Appearance	Appearance	planned
LE Role	LE Role	planned

This is the current state of the Link Layer implementation:

Aspect	Feature	Status
Roles	Slave Role	under construction
Master Role	not planned
Advertising	connectable undirected advertising	implemented
connectable directed advertising	planned
non-connectable undirected advertising	planned
scannable undirected advertising	planned
Device Filtering		not planned
Connections	Single Connection	implemented
Multiple Connection	not planned
Connection	Slave Latency	planned
Feature Support	LE Encryption	not planned
Connection Parameters Request Procedure	planned
Extended Reject Indication	planned
Slave-initiated Features Exchange	planned
LE Ping	implemented
LE Data Packet Length Extension	planned
LL Privacy	not planned
Extended Scanner Filter Policies	not planned

Pullrequests are wellcome.

Dependencies

• boost for Unittests
• CMake for build
• a decent C++ compiler supporting C++11
• btstack for experimental L2CAP support