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Data Structures | Public Types | Public Member Functions | Static Public Member Functions | Static Public Attributes
BLE Class Reference

Abstract away BLE-capable radio transceivers or SOCs. More...

#include <BLE.h>

Data Structures

struct  InitializationCompleteCallbackContext
 Initialization complete event. More...
struct  OnEventsToProcessCallbackContext
 Events to process event. More...

Public Types

typedef unsigned InstanceID_t
 Opaque type used to store the ID of a BLE instance. More...
typedef FunctionPointerWithContext< OnEventsToProcessCallbackContext * > OnEventsToProcessCallback_t
 Events to process event handler. More...
typedef void(* InitializationCompleteCallback_t) (InitializationCompleteCallbackContext *context)
 Initialization complete event handler. More...

Public Member Functions

InstanceID_t getInstanceID () const
 Fetch the ID of a BLE instance. More...
void onEventsToProcess (const OnEventsToProcessCallback_t &on_event_cb)
 Register a callback called when the BLE stack has pending work. More...
void processEvents ()
 Process ALL pending events living in the BLE stack and return once all events have been consumed. More...
ble_error_t init (InitializationCompleteCallback_t completion_cb=nullptr)
 Initialize the BLE controller/stack. More...
template<typename T >
ble_error_t init (T *object, void(T::*completion_cb)(InitializationCompleteCallbackContext *context))
 Initialize the BLE controller/stack. More...
bool hasInitialized () const
 Indicate if the BLE instance has been initialized. More...
ble_error_t shutdown ()
 Shut down the underlying stack, and reset state of this BLE instance. More...
const char * getVersion ()
 This call allows the application to get the BLE stack version information. More...
ble::Gapgap ()
 Accessor to Gap. More...
const ble::Gapgap () const
 A const alternative to gap(). More...
ble::GattServergattServer ()
 Accessor to GattServer. More...
const ble::GattServergattServer () const
 A const alternative to gattServer(). More...
ble::GattClientgattClient ()
 Accessors to GattClient. More...
const ble::GattClientgattClient () const
 A const alternative to gattClient(). More...
ble::SecurityManagersecurityManager ()
 Accessors to SecurityManager. More...
const ble::SecurityManagersecurityManager () const
 A const alternative to securityManager(). More...
void signalEventsToProcess ()
 This function allows the BLE stack to signal that there is work to do and event processing should be done (BLE::processEvent()). More...

Static Public Member Functions

static BLEInstance ()
 Get a reference to the BLE singleton. More...
static BLEInstance (InstanceID_t id)
 Get a reference to the BLE singleton corresponding to a given interface. More...
static const char * errorToString (ble_error_t error)
 Translate error code into a printable string. More...

Static Public Attributes

static const InstanceID_t DEFAULT_INSTANCE = 0
 The value of the BLE::InstanceID_t for the default BLE instance. More...
static const InstanceID_t NUM_INSTANCES = 1
 The number of permitted BLE instances for the application. More...

Detailed Description

Abstract away BLE-capable radio transceivers or SOCs.

Instances of this class have three responsibilities:

The user should not create BLE instances directly but rather access to the singleton(s) holding the BLE interfaces present in the system by using the static function Instance().

#include "ble/BLE.h"
BLE& ble_interface = BLE::Instance();

Next, the signal handling/process mechanism should be set up. By design, Mbed BLE does not impose to the user an event handling/processing mechanism; however, it exposes APIs, which allows an application to compose its own:

It is common to bind BLE event mechanism with Mbed EventQueue:

#include <events/mbed_events.h>
#include "ble/BLE.h"
// declare the event queue, which the whole application will share.
static EventQueue event_queue(4 * EVENTS_EVENT_SIZE);
// Function invoked when there is a BLE event available.
// Event processing is put into the event queue.
void schedule_ble_processing(BLE::OnEventsToProcessCallbackContext* context) {
event_queue.call(callback(&(context->ble), &BLE::processEvents));
int main()
BLE &ble_interface = BLE::Instance();
// Bind event signaling to schedule_ble_processing
// Launch BLE initialisation
// Dispatch events in the event queue
return 0;

Once the event processing mechanism is in place, the Bluetooth subsystem can be initialized with the init() function. That function accepts in input a callback, which will be invoked once the initialization process has finished.

void on_ble_init_complete(BLE::InitializationCompleteCallbackContext *context)
BLE& ble_interface = context->ble;
ble_error_t initialization_error = context->error;
if (initialization_error) {
// handle error
// The BLE interface can be accessed now.
int main() {
BLE &ble_interface = BLE::Instance();
// Initialize the BLE interface
return 0;

Definition at line 137 of file BLE.h.

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