AudioBLEServer Class Reference

A simple BLE server that implements the serial protocol, so that it can be used to send and recevie audio. In BLE terminologiy this is a Peripheral. This implementation uses the ArduinoBLE library! This is working only correctly if the client sets the max MTU to a value >= 256. Otherwise some of the transmitted information gets silently dropped. More...

#include <AudioBLEServer.h>

Inheritance diagram for AudioBLEServer:

Public Member Functions
	AudioBLEServer (int mtu=0)
	AudioBLEServer (int mtu=517)
virtual void	addNotifyAudioChange (AudioInfoSupport &bi)
	Adds target to be notified about audio changes.
virtual AudioInfo	audioInfo () override
	provides the actual input AudioInfo
virtual AudioInfo	audioInfoOut ()
int	available () override
int	available () override
int	availableForWrite () override
int	availableForWrite () override
virtual bool	begin ()
bool	begin (const char *name)
bool	begin (const char *name)
virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.
bool	connected () override
bool	connected () override
void	end () override
void	end () override
virtual void	flush () override
bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.
	operator bool ()
size_t	readBytes (uint8_t *data, size_t len) override
size_t	readBytes (uint8_t *data, size_t len) override
virtual size_t	readSilence (uint8_t *buffer, size_t length)
	Source to generate silence: just sets the buffer to 0.
virtual bool	removeNotifyAudioChange (AudioInfoSupport &bi)
	Removes a target in order not to be notified about audio changes.
void	setAudioInfo (AudioInfo info)
	Defines the input AudioInfo.
void	setAudioInfoActive (bool flag)
void	setAudioInfoUUID (const char *uuid)
void	setFramed (bool flag)
void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)
void	setRxUUID (const char *uuid)
void	setServiceUUID (const char *uuid)
void	setTxUUID (const char *uuid)
void	setWriteBufferSize (int size)
AudioInfo	toInfo (const uint8_t *str)
StrView	toStr (AudioInfo info)
size_t	write (const uint8_t *data, size_t dataSize) override
size_t	write (const uint8_t *data, size_t len) override
virtual size_t	write (uint8_t ch) override
virtual void	writeSilence (size_t len)
	Writes len bytes of silence (=0).

Protected Member Functions
bool	checkCentralConnected ()
int	getMTU () override
int	getMTU () override
size_t	getReadSize (size_t dataSize)
size_t	getReadSize (size_t dataSize)
virtual int	not_supported (int out, const char *msg="")
void	notifyAudioChange (AudioInfo info)
void	onConnect (BLEDevice device)
void	onConnect (BLEServer *pServer) override
void	onDisconnect (BLEDevice device)
void	onDisconnect (BLEServer *pServer) override
void	onRead (BLECharacteristic *pCharacteristic) override
	provide the next batch of audio data
void	onRead (BLECharacteristic characteristic)
	provide the next batch of audio data
void	onWrite (BLECharacteristic *pCharacteristic) override
	store the next batch of data
void	onWrite (BLECharacteristic characteristic)
	store the next batch of data
virtual void	receiveAudio (const uint8_t *data, size_t size)
virtual void	receiveAudio (const uint8_t *data, size_t size)
void	refillReadBuffer ()
	Refill small read buffer (e.g. 8 bytes) to avoid single byte reads when calling read()
virtual void	setAudioInfo (const uint8_t *data, size_t size)
void	setupBLEService ()
void	setupBLEService ()
void	setupRXBuffer ()
void	setupRXBuffer ()
void	setupTXBuffer ()
void	setupTXBuffer ()
void	writeAudioInfoCharacteristic (AudioInfo info)
void	writeAudioInfoCharacteristic (AudioInfo info)

Static Protected Member Functions
static void	bleOnRead (BLEDevice device, BLECharacteristic characteristic)
static void	bleOnWrite (BLEDevice device, BLECharacteristic characteristic)
static void	blePeripheralConnectHandler (BLEDevice device)
static void	blePeripheralDisconnectHandler (BLEDevice device)

Protected Attributes
int	_timeout = 10
char	audio_info_str [40]
const char *	BLE_AUDIO_SERVICE_UUID = "6e400001-b5a3-f393-e0a9-e50e24dcca9e"
const char *	BLE_CH1_UUID = "6e400002-b5a3-f393-e0a9-e50e24dcca9e"
const char *	BLE_CH2_UUID = "6e400003-b5a3-f393-e0a9-e50e24dcca9e"
const char *	BLE_INFO_UUID = "6e400004-b5a3-f393-e0a9-e50e24dcca9e"
const char *	ble_server_name = nullptr
BLEDevice	central
BLECharacteristic	ch01_char {BLE_CH1_UUID, BLERead, getMTU()}
BLECharacteristic *	ch01_char
BLEDescriptor	ch01_desc {"2901", "channel 1"}
BLECharacteristic	ch02_char {BLE_CH2_UUID, BLEWrite, getMTU()}
BLECharacteristic *	ch02_char
BLEDescriptor	ch02_desc {"2901", "channel 2"}
AudioInfo	info
BLECharacteristic	info_char
BLECharacteristic *	info_char
BLEDescriptor	info_desc {"2901", "info"}
bool	is_audio_info_active = false
bool	is_framed = false
bool	is_notify_active = true
bool	is_started = false
uint16_t	max_transfer_size = 0
Vector< AudioInfoSupport * >	notify_vector
BLEAdvertising *	p_advertising = nullptr
BLEServer *	p_server = nullptr
BLEService *	p_service = nullptr
RingBuffer< uint8_t >	receive_buffer {0}
RingBuffer< uint16_t >	receive_sizes {0}
BLEService	service {BLE_AUDIO_SERVICE_UUID}
RingBuffer< uint8_t >	tmp_in {0}
RingBuffer< uint8_t >	tmp_out {0}
RingBuffer< uint8_t >	transmit_buffer {0}
RingBuffer< uint16_t >	transmit_buffer_sizes {0}
int	write_buffer_size = MAX_SINGLE_CHARS

Detailed Description

A simple BLE server that implements the serial protocol, so that it can be used to send and recevie audio. In BLE terminologiy this is a Peripheral. This implementation uses the ArduinoBLE library! This is working only correctly if the client sets the max MTU to a value >= 256. Otherwise some of the transmitted information gets silently dropped.

A simple BLE server that implements the serial protocol, so that it can be used to send and recevie audio. In BLE terminologiy this is a Peripheral.

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

AudioBLEServer() [1/2]

AudioBLEServer ( int  mtu = 0 )

inline

AudioBLEServer() [2/2]

AudioBLEServer ( int  mtu = 517 )

inline

Member Function Documentation

addNotifyAudioChange()

virtual void addNotifyAudioChange ( AudioInfoSupport &  bi )

inlinevirtualinherited

Adds target to be notified about audio changes.

Reimplemented in CodecNOP, EncodedAudioOutput, EncodedAudioStream, AACDecoderFDK, DecoderBasic, CodecChain, MP3DecoderHelix, MP3DecoderMAD, OggContainerDecoder, RTSPClient< TcpClient, UdpSocket >, Pipeline, and Pipeline::ModifyingStreamAdapter.

audioInfo()

virtual AudioInfo audioInfo ( )

inlineoverridevirtualinherited

provides the actual input AudioInfo

Implements AudioInfoSupport.

Reimplemented in JupyterAudioT< T >, MozziStream, TimerCallbackAudioStream, EncodedAudioStream, PureDataStream, AdapterAudioOutputToAudioStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and InputMerge< T >.

audioInfoOut()

virtual AudioInfo audioInfoOut ( )

inlinevirtualinherited

provides the actual output AudioInfo: this is usually the same as audioInfo() unless we use a transforming stream

Reimplemented in MP3EncoderShine, PureDataStream, PWMAudioOutput< PWMDriverT >, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, FormatConverterStream, Pipeline, ResampleStream, and ResampleStreamT< TInterpolator >.

available() [1/2]

int available ( )

inlineoverridevirtual

Reimplemented from BaseStream.

available() [2/2]

int available ( )

inlineoverridevirtual

Reimplemented from BaseStream.

availableForWrite() [1/2]

int availableForWrite ( )

inlineoverridevirtual

Reimplemented from BaseStream.

availableForWrite() [2/2]

int availableForWrite ( )

inlineoverridevirtual

Reimplemented from BaseStream.

begin() [1/3]

virtual bool begin ( )

inlinevirtualinherited

Reimplemented in AudioOutputWithCallback, AudioMP34DT05, I2SCodecStream, MozziStream, PureDataStream, SPDIFOutput, VS1053Stream, WM8960Stream, AdaptiveResamplingStream, AudioLoRa, ESPNowStream, USBAudioDeviceBase, VBANStream, AudioEffectStreamT< T >, AudioEffectStream, Equalizer3Bands, Equalizer3BandsPerChannel, I2SStream, AudioStreamWrapper, TimerCallbackAudioStream, FrequencyDetectorAutoCorrelation, GoertzelStream, ResampleStreamT< TInterpolator >, FileLoopT< FileType >, FileLoopT< File >, EncodedAudioStream, AudioBoardStream, AudioKitStream, MiniAudioStream, PortAudioStream, StdioStream, HLSStreamT< URLStream >, NRF24Stream, AnalogAudioStream, AdapterAudioOutputToAudioStream, TimedStream, MemoryStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, MeasuringStream, ProgressStream, Throttle, InputMerge< T >, CallbackStream, FilteredStream< T, TF >, FilteredStream< int16_t, int16_t >, VolumeMeter, AudioInputMonitor, ChannelFormatConverterStreamT< T >, ChannelFormatConverterStream, NumberFormatConverterStreamT< TFrom, TTo >, NumberFormatConverterStream, FormatConverterStream, CatStream, QueueStream< T >, QueueStream< uint8_t >, DynamicMemoryStream, Pipeline, Pipeline::ModifyingStreamAdapter, QualityAnalysisStream, ResampleStream, VolumeStream, AudioFFTBase, and EqualizerNBands< SampleT, AccT, NUM_TAPS, NUM_BANDS >.

begin() [2/3]

bool begin ( const char *  name )

inline

begin() [3/3]

bool begin ( const char *  name )

inline

bleOnRead()

static void bleOnRead ( BLEDevice  device, BLECharacteristic  characteristic  )

inlinestaticprotected

bleOnWrite()

static void bleOnWrite ( BLEDevice  device, BLECharacteristic  characteristic  )

inlinestaticprotected

blePeripheralConnectHandler()

static void blePeripheralConnectHandler ( BLEDevice  device )

inlinestaticprotected

blePeripheralDisconnectHandler()

static void blePeripheralDisconnectHandler ( BLEDevice  device )

inlinestaticprotected

checkCentralConnected()

bool checkCentralConnected ( )

inlineprotected

clearNotifyAudioChange()

virtual void clearNotifyAudioChange ( )

inlinevirtualinherited

Deletes all change notify subscriptions.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

connected() [1/2]

bool connected ( )

inlineoverridevirtual

Implements AudioBLEStream.

connected() [2/2]

bool connected ( )

inlineoverridevirtual

Implements AudioBLEStream.

end() [1/2]

void end ( )

inlineoverridevirtual

Implements AudioBLEStream.

end() [2/2]

void end ( )

inlineoverridevirtual

Implements AudioBLEStream.

flush()

virtual void flush ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in PureDataStream, URLStreamBufferedT< T >, URLStreamBufferedT< ICYStream >, ReformatBaseStream, AudioStreamWrapper, ResampleStream, EncodedAudioStream, URLStream, BufferedTaskStream, I2SStream, MemoryStream, RingBufferStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, and BufferedStream.

getMTU() [1/2]

int getMTU ( )

inlineoverrideprotectedvirtual

Implements AudioBLEStream.

getMTU() [2/2]

int getMTU ( )

inlineoverrideprotectedvirtual

Implements AudioBLEStream.

getReadSize() [1/2]

size_t getReadSize ( size_t  dataSize )

inlineprotected

getReadSize() [2/2]

size_t getReadSize ( size_t  dataSize )

inlineprotected

isNotifyActive()

bool isNotifyActive ( )

inlineinherited

Checks if the automatic AudioInfo update is active.

not_supported()

virtual int not_supported ( int  out, const char *  msg = ""  )

inlineprotectedvirtualinherited

notifyAudioChange()

void notifyAudioChange ( AudioInfo  info )

inlineprotectedinherited

onConnect() [1/2]

void onConnect ( BLEDevice  device )

inlineprotected

onConnect() [2/2]

void onConnect ( BLEServer *  pServer )

inlineoverrideprotected

onDisconnect() [1/2]

void onDisconnect ( BLEDevice  device )

inlineprotected

onDisconnect() [2/2]

void onDisconnect ( BLEServer *  pServer )

inlineoverrideprotected

onRead() [1/2]

void onRead ( BLECharacteristic *  pCharacteristic )

inlineoverrideprotected

provide the next batch of audio data

onRead() [2/2]

void onRead ( BLECharacteristic  characteristic )

inlineprotected

provide the next batch of audio data

onWrite() [1/2]

void onWrite ( BLECharacteristic *  pCharacteristic )

inlineoverrideprotected

store the next batch of data

onWrite() [2/2]

void onWrite ( BLECharacteristic  characteristic )

inlineprotected

store the next batch of data

operator bool()

operator bool ( )

inlinevirtualinherited

Reimplemented from AudioStream.

readBytes() [1/2]

size_t readBytes ( uint8_t *  data, size_t  len  )

inlineoverridevirtual

Reimplemented from AudioStream.

readBytes() [2/2]

size_t readBytes ( uint8_t *  data, size_t  len  )

inlineoverridevirtual

Reimplemented from AudioStream.

readSilence()

virtual size_t readSilence ( uint8_t *  buffer, size_t  length  )

inlinevirtualinherited

Source to generate silence: just sets the buffer to 0.

receiveAudio() [1/2]

virtual void receiveAudio ( const uint8_t *  data, size_t  size  )

inlineprotectedvirtual

receiveAudio() [2/2]

virtual void receiveAudio ( const uint8_t *  data, size_t  size  )

inlineprotectedvirtual

refillReadBuffer()

void refillReadBuffer ( )

inlineprotectedinherited

Refill small read buffer (e.g. 8 bytes) to avoid single byte reads when calling read()

removeNotifyAudioChange()

virtual bool removeNotifyAudioChange ( AudioInfoSupport &  bi )

inlinevirtualinherited

Removes a target in order not to be notified about audio changes.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

setAudioInfo() [1/2]

void setAudioInfo ( AudioInfo  info )

inlinevirtualinherited

Defines the input AudioInfo.

Reimplemented from AudioStream.

setAudioInfo() [2/2]

virtual void setAudioInfo ( const uint8_t *  data, size_t  size  )

inlineprotectedvirtualinherited

setAudioInfoActive()

void setAudioInfoActive ( bool  flag )

inlineinherited

setAudioInfoUUID()

void setAudioInfoUUID ( const char *  uuid )

inlineinherited

setFramed()

void setFramed ( bool  flag )

inlineinherited

setNotifyActive()

void setNotifyActive ( bool  flag )

inlineinherited

Deactivate/Reactivate automatic AudioInfo updates: (default is active)

setRxUUID()

void setRxUUID ( const char *  uuid )

inlineinherited

setServiceUUID()

void setServiceUUID ( const char *  uuid )

inlineinherited

setTxUUID()

void setTxUUID ( const char *  uuid )

inlineinherited

setupBLEService() [1/2]

void setupBLEService ( )

inlineprotected

setupBLEService() [2/2]

void setupBLEService ( )

inlineprotected

setupRXBuffer() [1/2]

void setupRXBuffer ( )

inlineprotected

setupRXBuffer() [2/2]

void setupRXBuffer ( )

inlineprotected

setupTXBuffer() [1/2]

void setupTXBuffer ( )

inlineprotected

setupTXBuffer() [2/2]

void setupTXBuffer ( )

inlineprotected

setWriteBufferSize()

void setWriteBufferSize ( int  size )

inlineinherited

toInfo()

AudioInfo toInfo ( const uint8_t *  str )

inlineinherited

toStr()

StrView toStr ( AudioInfo  info )

inlineinherited

write() [1/3]

size_t write ( const uint8_t *  data, size_t  dataSize  )

inlineoverridevirtual

Reimplemented from AudioStream.

write() [2/3]

size_t write ( const uint8_t *  data, size_t  len  )

inlineoverridevirtual

Reimplemented from AudioStream.

write() [3/3]

virtual size_t write ( uint8_t  ch )

inlineoverridevirtualinherited

Reimplemented in MemoryStream, AudioStreamWrapper, BufferedTaskStream, RingBufferStream, BufferedStream, and URLStream.

writeAudioInfoCharacteristic() [1/2]

void writeAudioInfoCharacteristic ( AudioInfo  info )

inlineprotectedvirtual

Implements AudioBLEStream.

writeAudioInfoCharacteristic() [2/2]

void writeAudioInfoCharacteristic ( AudioInfo  info )

inlineprotectedvirtual

Implements AudioBLEStream.

writeSilence()

virtual void writeSilence ( size_t  len )

inlinevirtualinherited

Writes len bytes of silence (=0).

Member Data Documentation

_timeout

int _timeout = 10

protectedinherited

audio_info_str

char audio_info_str[40]

protectedinherited

BLE_AUDIO_SERVICE_UUID

const char* BLE_AUDIO_SERVICE_UUID = "6e400001-b5a3-f393-e0a9-e50e24dcca9e"

protectedinherited

BLE_CH1_UUID

const char* BLE_CH1_UUID = "6e400002-b5a3-f393-e0a9-e50e24dcca9e"

protectedinherited

BLE_CH2_UUID

const char* BLE_CH2_UUID = "6e400003-b5a3-f393-e0a9-e50e24dcca9e"

protectedinherited

BLE_INFO_UUID

const char* BLE_INFO_UUID = "6e400004-b5a3-f393-e0a9-e50e24dcca9e"

protectedinherited

ble_server_name

const char* ble_server_name = nullptr

protectedinherited

central

BLEDevice central

protected

ch01_char [1/2]

BLECharacteristic ch01_char {BLE_CH1_UUID, BLERead, getMTU()}

protected

ch01_char [2/2]

BLECharacteristic* ch01_char

protected

ch01_desc

BLEDescriptor ch01_desc {"2901", "channel 1"}

protected

ch02_char [1/2]

BLECharacteristic ch02_char {BLE_CH2_UUID, BLEWrite, getMTU()}

protected

ch02_char [2/2]

BLECharacteristic* ch02_char

protected

ch02_desc

BLEDescriptor ch02_desc {"2901", "channel 2"}

protected

info

AudioInfo info

protectedinherited

info_char [1/2]

BLECharacteristic info_char

protected

Initial value:

{BLE_INFO_UUID, BLERead | BLEWrite | BLENotify,
                              80}

info_char [2/2]

BLECharacteristic* info_char

protected

info_desc

BLEDescriptor info_desc {"2901", "info"}

protected

is_audio_info_active

bool is_audio_info_active = false

protectedinherited

is_framed

bool is_framed = false

protectedinherited

is_notify_active

bool is_notify_active = true

protectedinherited

is_started

bool is_started = false

protectedinherited

max_transfer_size

uint16_t max_transfer_size = 0

protectedinherited

notify_vector

Vector<AudioInfoSupport*> notify_vector

protectedinherited

p_advertising

BLEAdvertising* p_advertising = nullptr

protected

p_server

BLEServer* p_server = nullptr

protected

p_service

BLEService* p_service = nullptr

protected

receive_buffer

RingBuffer< uint8_t > receive_buffer {0}

protected

receive_sizes

RingBuffer< uint16_t > receive_sizes {0}

protected

service

BLEService service {BLE_AUDIO_SERVICE_UUID}

protected

tmp_in

RingBuffer<uint8_t> tmp_in {0}

protectedinherited

tmp_out

RingBuffer<uint8_t> tmp_out {0}

protectedinherited

transmit_buffer

RingBuffer< uint8_t > transmit_buffer {0}

protected

transmit_buffer_sizes

RingBuffer< uint16_t > transmit_buffer_sizes {0}

protected

write_buffer_size

int write_buffer_size = MAX_SINGLE_CHARS

protectedinherited

---

The documentation for this class was generated from the following files:

• src/AudioTools/Sandbox/BLE/AudioBLEServer.h
• src/AudioTools/Sandbox/BLE/AudioBLEServerESP32.h