BLESerialClientESP32 Class Reference

A BLE client that implements a serial protocol, so that it can be used to send and receive audio. In BLE terminology this is a Central. This implementation uses the BLE library of the ESP32 Arduino core (Bluedroid or NimBLE). More...

#include <BLESerialClientESP32.h>

Inheritance diagram for BLESerialClientESP32:

Collaboration diagram for BLESerialClientESP32:

Public Member Functions
	BLESerialClientESP32 (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	availableForWrite () override
virtual bool	begin ()
bool	begin (const char *localName, int seconds)
virtual void	clearNotifyAudioChange ()
	Deletes all change notify subscriptions.
bool	connected () override
	Returns true if we are connected with the other side.
void	end () override
void	flush () override
	Sends the buffered data which does not fill a complete packet.
bool	isNotifyActive ()
	Checks if the automatic AudioInfo update is active.
	operator bool () override
int	packetSize ()
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 newInfo) override
void	setAudioInfoActive (bool flag)
	Activates the exchange of the audio info.
void	setAudioInfoUUID (const char *uuid)
	Defines the UUID of the audio info characteristic.
void	setConfirmWrite (bool flag)
	Writes with response: slower but with flow control.
void	setFramed (bool flag)
	Keeps the write sizes: each write is one BLE packet.
void	setMTU (int mtu)
	Defines the requested MTU (must be called before begin)
void	setNotifyActive (bool flag)
	Deactivate/Reactivate automatic AudioInfo updates: (default is active)
void	setRxBufferSize (int bytes, int packets=100)
void	setRxUUID (const char *uuid)
	Defines the UUID of the characteristic which is written by the client.
void	setServiceUUID (const char *uuid)
	Defines the service UUID.
void	setTxBufferSize (int bytes, int packets=100)
void	setTxUUID (const char *uuid)
	Defines the UUID of the characteristic which is read by the client.
void	setWriteBufferSize (int size)
void	setWriteThrottle (int ms)
	Waits the indicated ms after each write.
AudioInfo	toInfo (const uint8_t *data, size_t len)
	Converts the string from the info characteristic to the audio info.
StrView	toStr (AudioInfo info)
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	connect () override
	Connects to the server if it was found: returns true if successful.
int	getMTU () override
	Effective MTU.
bool	isConnected () override
	Returns true if we are connected.
virtual int	not_supported (int out, const char *msg="")
void	notifyAudioChange (AudioInfo info)
void	onConnect (BLEClient *pClient) override
void	onConnected ()
	Common setup after the connection was established.
void	onDisconnect (BLEClient *pClient) override
void	onResult (BLEAdvertisedDevice advertisedDevice) override
	scanning results
bool	readAudioInfo () override
	Requests the audio info from the server: returns true if successful.
int	readPacket (uint8_t *data, int maxLen) override
	Reads the next packet (incl. header) from the server: returns the size.
void	receiveAudioInfo (const uint8_t *data, size_t size)
	Process the audio info which was received from the other side.
void	receivePacket ()
	Reads the next packet from the server into the receive buffer.
bool	reconnectLater ()
	disconnect and scan again
void	refillReadBuffer ()
	Refill small read buffer (e.g. 8 bytes) to avoid single byte reads when calling read()
bool	sendPacket (const uint8_t *data, size_t len)
bool	startClient (const char *localName) override
	Starts BLE and the scanning for the server.
void	startScan ()
void	writeAudioInfo (StrView str) override
	Provides the audio info to the other side.
bool	writePacket (const uint8_t *data, int len) override
	Writes a packet to the server.

Static Protected Member Functions
static int	getHeader (const uint8_t *packet, int packetLen)
	Determines the payload length from the 2 byte header.
static void	notifyCallback (BLERemoteCharacteristic *characteristic, uint8_t *data, size_t length, bool isNotify)
static BLESerialClientESP32 *&	selfBLESerialClientESP32 ()
static void	setHeader (uint8_t *packet, int len)
	Copies the payload length into the 2 byte header.

Protected Attributes
int	_timeout = 10
BLEAdvertisedDevice	advertised_device
char	audio_info_str [40]
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_SERIAL_SERVICE_UUID = "6e400001-b5a3-f393-e0a9-e50e24dcca9e"
BLERemoteCharacteristic *	ch01_char = nullptr
BLERemoteCharacteristic *	ch02_char = nullptr
AudioInfo	info
BLERemoteCharacteristic *	info_char = nullptr
bool	is_audio_info_active = false
bool	is_audio_info_defined = false
volatile bool	is_found = false
bool	is_framed = false
bool	is_notify_active = true
volatile bool	is_setup = false
bool	is_started = false
int	max_transfer_size = 0
Vector< AudioInfoSupport * >	notify_vector
BLEClient *	p_client = nullptr
Vector< uint8_t >	read_packet {0}
BLESerialPacketBuffer	rx_buffer
int	rx_buffer_size = 4096
Mutex	rx_mutex
int	rx_packet_count = 100
RingBuffer< uint8_t >	tmp_in {0}
RingBuffer< uint8_t >	tmp_out {0}
int	tx_buffer_size = 4096
int	tx_packet_count = 100
SingleBuffer< uint8_t >	write_buffer {0}
int	write_buffer_size = MAX_SINGLE_CHARS
bool	write_confirmation_flag = false
int	write_throttle = 0

Detailed Description

A BLE client that implements a serial protocol, so that it can be used to send and receive audio. In BLE terminology this is a Central. This implementation uses the BLE library of the ESP32 Arduino core (Bluedroid or NimBLE).

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

BLESerialClientESP32()

BLESerialClientESP32 ( 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, ResampleStreamT< TInterpolator >, and SupportedRatesStream.

available()

int available ( )

inlineoverridevirtualinherited

Reimplemented from BaseStream.

availableForWrite()

int availableForWrite ( )

inlineoverridevirtualinherited

Reimplemented from BaseStream.

begin() [1/2]

virtual bool begin ( )

inlinevirtualinherited

Reimplemented in AudioOutputWithCallback, AudioMP34DT05, I2SCodecStream, MozziStream, PureDataStream, SPDIFOutput, VS1053Stream, WM8960Stream, AdaptiveResamplingStream, AudioLoRa, ESPNowStream, USBAudioDeviceBase, USBAudioHostBase, VBANStream, FrequencyDetectorAutoCorrelation, GoertzelStream, AudioEffectStreamT< T >, AudioEffectStream, Equalizer3BandsT< T >, Equalizer3BandsPerChannelT< T >, I2SStream, AudioTimeSourceStream, AudioStreamWrapper, TimerCallbackAudioStream, ResampleStreamT< TInterpolator >, FileLoopT< FileType >, FileLoopT< File >, EncodedAudioStream, AudioBoardStream, AudioKitStream, MiniAudioStream, PortAudioStream, StdioStream, HLSStreamT< URLStream >, NRF24Stream, ReedSolomonFEC< bytecount, additional_bytes >, AutomaticGainControlStream, MeasuringStream, QualityAnalysisStream, VolumeStream, AnalogAudioStream, AdapterAudioOutputToAudioStream, TimedStream, MemoryStream, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, 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, ResampleStream, SupportedRatesStream, AudioFFTBase, and EqualizerNBands< SampleT, AccT, NUM_TAPS, NUM_BANDS >.

begin() [2/2]

bool begin ( const char *  localName, int  seconds  )

inlineinherited

Starts the BLE client and waits at most the indicated seconds for the connection to the server. With 0 seconds we connect in the background.

clearNotifyAudioChange()

virtual void clearNotifyAudioChange ( )

inlinevirtualinherited

Deletes all change notify subscriptions.

Reimplemented in RTSPClient< TcpClient, UdpSocket >.

connect()

bool connect ( )

inlineoverrideprotectedvirtual

Connects to the server if it was found: returns true if successful.

Implements BLESerialClientBase.

connected()

bool connected ( )

inlineoverridevirtualinherited

Returns true if we are connected with the other side.

Implements BLESerialStream.

end()

void end ( )

inlineoverridevirtual

Implements BLESerialStream.

flush()

void flush ( )

inlineoverridevirtualinherited

Sends the buffered data which does not fill a complete packet.

Reimplemented from BaseStream.

getHeader()

static int getHeader ( const uint8_t *  packet, int  packetLen  )

inlinestaticprotectedinherited

Determines the payload length from the 2 byte header.

getMTU()

int getMTU ( )

inlineoverrideprotectedvirtual

Effective MTU.

Reimplemented from BLESerialStream.

isConnected()

bool isConnected ( )

inlineoverrideprotectedvirtual

Returns true if we are connected.

Implements BLESerialClientBase.

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

notifyCallback()

static void notifyCallback ( BLERemoteCharacteristic *  characteristic, uint8_t *  data, size_t  length, bool  isNotify  )

inlinestaticprotected

onConnect()

void onConnect ( BLEClient *  pClient )

inlineoverrideprotected

onConnected()

void onConnected ( )

inlineprotectedinherited

Common setup after the connection was established.

onDisconnect()

void onDisconnect ( BLEClient *  pClient )

inlineoverrideprotected

onResult()

void onResult ( BLEAdvertisedDevice  advertisedDevice )

inlineoverrideprotected

scanning results

operator bool()

operator bool ( )

inlineoverridevirtualinherited

Reimplemented from AudioStream.

packetSize()

int packetSize ( )

inlineinherited

Max number of payload bytes in one BLE packet: the packets read by the client also contain the length header and a value can not be longer than 512 bytes

readAudioInfo()

bool readAudioInfo ( )

inlineoverrideprotectedvirtual

Requests the audio info from the server: returns true if successful.

Implements BLESerialClientBase.

readBytes()

size_t readBytes ( uint8_t *  data, size_t  len  )

inlineoverridevirtualinherited

Reimplemented from AudioStream.

readPacket()

int readPacket ( uint8_t *  data, int  maxLen  )

inlineoverrideprotectedvirtual

Reads the next packet (incl. header) from the server: returns the size.

Implements BLESerialClientBase.

readSilence()

virtual size_t readSilence ( uint8_t *  buffer, size_t  length  )

inlinevirtualinherited

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

receiveAudioInfo()

void receiveAudioInfo ( const uint8_t *  data, size_t  size  )

inlineprotectedinherited

Process the audio info which was received from the other side.

receivePacket()

void receivePacket ( )

inlineprotectedinherited

Reads the next packet from the server into the receive buffer.

reconnectLater()

bool reconnectLater ( )

inlineprotected

disconnect and scan again

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 >.

selfBLESerialClientESP32()

static BLESerialClientESP32 *& selfBLESerialClientESP32 ( )

inlinestaticprotected

sendPacket()

bool sendPacket ( const uint8_t *  data, size_t  len  )

inlineprotectedinherited

setAudioInfo()

void setAudioInfo ( AudioInfo  newInfo )

inlineoverridevirtualinherited

Defines the audio info and informs the other side if setAudioInfoActive(true) was called

Reimplemented from AudioStream.

setAudioInfoActive()

void setAudioInfoActive ( bool  flag )

inlineinherited

Activates the exchange of the audio info.

setAudioInfoUUID()

void setAudioInfoUUID ( const char *  uuid )

inlineinherited

Defines the UUID of the audio info characteristic.

setConfirmWrite()

void setConfirmWrite ( bool  flag )

inlineinherited

Writes with response: slower but with flow control.

setFramed()

void setFramed ( bool  flag )

inlineinherited

Keeps the write sizes: each write is one BLE packet.

setHeader()

static void setHeader ( uint8_t *  packet, int  len  )

inlinestaticprotectedinherited

Copies the payload length into the 2 byte header.

setMTU()

void setMTU ( int  mtu )

inlineinherited

Defines the requested MTU (must be called before begin)

setNotifyActive()

void setNotifyActive ( bool  flag )

inlineinherited

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

setRxBufferSize()

void setRxBufferSize ( int  bytes, int  packets = 100  )

inlineinherited

Defines the size of the receive buffer and (in framed mode) the max number of packets: must be called before begin

setRxUUID()

void setRxUUID ( const char *  uuid )

inlineinherited

Defines the UUID of the characteristic which is written by the client.

setServiceUUID()

void setServiceUUID ( const char *  uuid )

inlineinherited

Defines the service UUID.

setTxBufferSize()

void setTxBufferSize ( int  bytes, int  packets = 100  )

inlineinherited

Defines the size of the transmit buffer and (in framed mode) the max number of packets: must be called before begin

setTxUUID()

void setTxUUID ( const char *  uuid )

inlineinherited

Defines the UUID of the characteristic which is read by the client.

setWriteBufferSize()

void setWriteBufferSize ( int  size )

inlineinherited

setWriteThrottle()

void setWriteThrottle ( int  ms )

inlineinherited

Waits the indicated ms after each write.

startClient()

bool startClient ( const char *  localName )

inlineoverrideprotectedvirtual

Starts BLE and the scanning for the server.

Implements BLESerialClientBase.

startScan()

void startScan ( )

inlineprotected

toInfo()

AudioInfo toInfo ( const uint8_t *  data, size_t  len  )

inlineinherited

Converts the string from the info characteristic to the audio info.

toStr()

StrView toStr ( AudioInfo  info )

inlineinherited

Converts the audio info to the string which is used in the info characteristic

write() [1/2]

size_t write ( const uint8_t *  data, size_t  len  )

inlineoverridevirtualinherited

Reimplemented from AudioStream.

write() [2/2]

virtual size_t write ( uint8_t  ch )

inlineoverridevirtualinherited

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

writeAudioInfo()

void writeAudioInfo ( StrView  info )

inlineoverrideprotectedvirtual

Provides the audio info to the other side.

Implements BLESerialStream.

writePacket()

bool writePacket ( const uint8_t *  data, int  len  )

inlineoverrideprotectedvirtual

Writes a packet to the server.

Implements BLESerialClientBase.

writeSilence()

virtual void writeSilence ( size_t  len )

inlinevirtualinherited

Writes len bytes of silence (=0).

Member Data Documentation

_timeout

int _timeout = 10

protectedinherited

advertised_device

BLEAdvertisedDevice advertised_device

protected

audio_info_str

char audio_info_str[40]

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_SERIAL_SERVICE_UUID

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

protectedinherited

ch01_char

BLERemoteCharacteristic* ch01_char = nullptr

protected

ch02_char

BLERemoteCharacteristic* ch02_char = nullptr

protected

info

AudioInfo info

protectedinherited

info_char

BLERemoteCharacteristic* info_char = nullptr

protected

is_audio_info_active

bool is_audio_info_active = false

protectedinherited

is_audio_info_defined

bool is_audio_info_defined = false

protectedinherited

is_found

volatile bool is_found = false

protected

is_framed

bool is_framed = false

protectedinherited

is_notify_active

bool is_notify_active = true

protectedinherited

is_setup

volatile bool is_setup = false

protected

is_started

bool is_started = false

protectedinherited

max_transfer_size

int max_transfer_size = 0

protectedinherited

notify_vector

Vector<AudioInfoSupport*> notify_vector

protectedinherited

p_client

BLEClient* p_client = nullptr

protected

read_packet

Vector<uint8_t> read_packet {0}

protectedinherited

rx_buffer

BLESerialPacketBuffer rx_buffer

protectedinherited

rx_buffer_size

int rx_buffer_size = 4096

protectedinherited

rx_mutex

Mutex rx_mutex

protected

rx_packet_count

int rx_packet_count = 100

protectedinherited

tmp_in

RingBuffer<uint8_t> tmp_in {0}

protectedinherited

tmp_out

RingBuffer<uint8_t> tmp_out {0}

protectedinherited

tx_buffer_size

int tx_buffer_size = 4096

protectedinherited

tx_packet_count

int tx_packet_count = 100

protectedinherited

write_buffer

SingleBuffer<uint8_t> write_buffer {0}

protectedinherited

write_buffer_size

int write_buffer_size = MAX_SINGLE_CHARS

protectedinherited

write_confirmation_flag

bool write_confirmation_flag = false

protectedinherited

write_throttle

int write_throttle = 0

protectedinherited

---

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

• src/AudioTools/Communication/BLESerial/BLESerialClientESP32.h