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 a complete example of a small GATT server, that allows a client to controll an IO pin, running on a nrf51422:
#include <bluetoe/server.hpp>
#include <bluetoe/bindings/nrf51.hpp>
#include <nrf.h>
using namespace bluetoe;
static constexpr int io_pin = 19;
static std::uint8_t io_pin_write_handler( bool state )
{
// the GPIO pin according to the received value: 0 = off, 1 = on
NRF_GPIO->OUT = state
? NRF_GPIO->OUT | ( 1 << io_pin )
: NRF_GPIO->OUT & ~( 1 << io_pin );
return error_codes::success;
}
typedef server<
service<
service_uuid< 0xC11169E1, 0x6252, 0x4450, 0x931C, 0x1B43A318783B >,
characteristic<
free_write_handler< bool, io_pin_write_handler >
>
>
> blinky_server;
blinky_server gatt;
nrf51< blinky_server > gatt_srv;
int main()
{
// Init GPIO pin
NRF_GPIO->PIN_CNF[ io_pin ] =
( GPIO_PIN_CNF_DRIVE_S0H1 << GPIO_PIN_CNF_DRIVE_Pos ) |
( GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos );
for ( ;; )
gatt_srv.run( gatt );
}
http://torstenrobitzki.github.io/bluetoe/
Bluetoe ships with its own link layer. Currently a link layer based on the nrf51422 is under construction and is already usable. 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).
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 |
| Declare Secondary 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 | implemented |
| 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 | implemented |
| Complete List of 16-bit Service UUIDs | implemented | |
| Incomplete List of 32-bit Service UUIDs | not planned | |
| Complete List of 32-bit Service UUIDs | not planned | |
| Incomplete List of 128-bit Service UUIDs | implemented | |
| Complete List of 128-bit Service UUIDs | implemented | |
| Local Name | Shortened Local Name | implemented |
| Complete Local Name | implemented | |
| Flags | Flags | implemented |
| 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 | implemented |
| LE Role | LE Role | planned |
This is the current state of the Link Layer implementation:
| Aspect | Feature | Status |
|---|---|---|
| Roles | Slave Role | implemented |
| Master Role | not planned | |
| Advertising | connectable undirected advertising | implemented |
| connectable directed advertising | implemented | |
| non-connectable undirected advertising | implemented | |
| scannable undirected advertising | implemented | |
| Device Filtering | implemented | |
| Connections | Single Connection | implemented |
| Multiple Connection | not planned | |
| Connection | Slave Latency | planned |
| Feature Support | LE Encryption | 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.
- boost for Unittests
- CMake for build
- a decent C++ compiler supporting C++11