ESPNowStream Class Reference

ESPNow as Arduino Stream. When use_send_ack is true we prevent any buffer overflows by blocking writes until the previous packet has been confirmed. When no acknowledgments are used, you might need to throttle the send speed to prevent any buffer overflow on the receiver side. More...

#include <ESPNowStream.h>

Inheritance diagram for ESPNowStream:

Public Member Functions
	ESPNowStream ()
	~ESPNowStream ()
bool	addBroadcastPeer ()
bool	addPeer (const char *address)
	Adds a peer to which we can send info or from which we can receive info.
bool	addPeer (const uint8_t *address)
	Adds a peer to which we can send info or from which we can receive info.
bool	addPeer (esp_now_peer_info_t &peer)
	Adds a peer to which we can send info or from which we can receive info.
template<size_t size>
bool	addPeers (const char *(&array)[size])
	Adds an array of peers.
template<size_t N>
bool	addPeers (const uint8_t(&array)[N][6])
	Adds an array of peers.
int	available () override
int	availableForWrite () override
bool	begin ()
	Initialization of ESPNow.
virtual bool	begin (ESPNowStreamConfig cfg)
	Initialization of ESPNow incl WIFI.
bool	clearPeers ()
	Deletes all registered peers.
ESPNowStreamConfig	defaultConfig ()
virtual void	end ()
	DeInitialization.
virtual void	flush () override
virtual void	flush () override
BufferRTOS< uint8_t > &	getBuffer ()
	provides access to the receive buffer
float	getBufferPercent ()
	provides how much the receive buffer is filled (in percent)
uint8_t	getChannel ()
	Provides the WiFi Channel.
uint32_t	getLastIoSuccessTime () const
	time when we were able to send or receive the last packet successfully
const char *	macAddress ()
	Returns the mac address of the current ESP32.
	operator bool ()
	operator bool ()
size_t	readBytes (uint8_t *data, size_t len) override
	Reeds the data from the peers.
void	setChannel (uint8_t ch)
	Defines the WiFi Channel.
void	setReceiveCallback (esp_now_recv_cb_t cb)
void	setSendCallback (esp_now_send_cb_t cb)
	Defines an alternative send callback.
void	setWriteBufferSize (int size)
void	setWriteBufferSize (int size)
virtual size_t	write (uint8_t ch) override
size_t	write (const char *peer, const uint8_t *data, size_t len)
	Writes the data - sends it to all the indicated peer mac address string.
size_t	write (const uint8_t *data, size_t len) override
	Writes the data - sends it to all registered peers.
size_t	write (const uint8_t *peer, const uint8_t *data, size_t len)
	Writes the data - sends it to all the peers.

Protected Member Functions
wifi_interface_t	getInterface ()
virtual void	handle_recv_cb (const uint8_t *mac_addr, const uint8_t *data, int data_len, bool broadcast, uint8_t rssi)
virtual void	handle_send_cb (const uint8_t *mac_addr, esp_now_send_status_t status)
bool	handleQueueError (esp_err_t rc, int &retry_count)
	Handles errors when queuing packets.
bool	handleTransmissionResult (int &retry_count)
	Handles the result of packet transmission (after queuing).
bool	initWiFi (wifi_mode_t mode)
bool	isEncrypted ()
const char *	mac2str (const uint8_t *array)
void	refillReadBuffer ()
	Refill small read buffer (e.g. 8 bytes) to avoid single byte reads when calling read().
void	refillReadBuffer ()
	Refill small read buffer (e.g. 8 bytes) to avoid single byte reads when calling read().
void	resetAvailableToWrite ()
virtual bool	sendPacket (const uint8_t *data, size_t len, int &retry_count, const uint8_t *destination=nullptr)
	Sends a single packet with retry logic.
bool	setup ()
	Initialization.
bool	setupMAC ()
void	setupReceiveBuffer ()
void	setupSemaphore ()
bool	setupWiFi ()
bool	str2mac (const char *mac, uint8_t *values)

Static Protected Member Functions
static int	bufferAvailableForWrite ()
static void	default_recv_cb (const esp_now_recv_info *info, const uint8_t *data, int data_len)
static void	default_send_cb (const wifi_tx_info_t *tx_info, esp_now_send_status_t status)

Protected Attributes
int	_timeout = 10
volatile size_t	available_to_write = 0
BufferRTOS< uint8_t >	buffer {0}
ESPNowStreamConfig	cfg
bool	has_peers = false
bool	is_broadcast = false
bool	is_init = false
uint32_t	last_io_success_time = 0
volatile bool	last_send_success = true
bool	read_ready = false
esp_now_recv_cb_t	receive = default_recv_cb
esp_now_send_cb_t	send = default_send_cb
RingBuffer< uint8_t >	tmp_in {0}
RingBuffer< uint8_t >	tmp_out {0}
int	write_buffer_size = 8
SemaphoreHandle_t	xSemaphore = nullptr

Detailed Description

ESPNow as Arduino Stream. When use_send_ack is true we prevent any buffer overflows by blocking writes until the previous packet has been confirmed. When no acknowledgments are used, you might need to throttle the send speed to prevent any buffer overflow on the receiver side.

Note

If multiple receivers are in range, only the first one which sends an acknowledgment will be used as coordinator.

Author

Phil Schatzmann

Copyright

GPLv3

Constructor & Destructor Documentation

ESPNowStream()

ESPNowStream ( )

inline

~ESPNowStream()

~ESPNowStream ( )

inline

Member Function Documentation

addBroadcastPeer()

bool addBroadcastPeer ( )

inline

Adds the broadcast peer (FF:FF:FF:FF:FF:FF) to send to all devices in range. Note: Broadcast does not support acknowledgments

addPeer() [1/3]

bool addPeer ( const char * address )

inline

Adds a peer to which we can send info or from which we can receive info.

addPeer() [2/3]

bool addPeer ( const uint8_t * address )

inline

Adds a peer to which we can send info or from which we can receive info.

addPeer() [3/3]

bool addPeer ( esp_now_peer_info_t & peer )

inline

Adds a peer to which we can send info or from which we can receive info.

addPeers() [1/2]

template<size_t size>

bool addPeers ( const char *(&) array[size] )

inline

Adds an array of peers.

addPeers() [2/2]

template<size_t N>

bool addPeers ( const uint8_t(&) array[N][6] )

inline

Adds an array of peers.

available()

int available ( )

inlineoverridevirtual

Reimplemented from BaseStream.

availableForWrite()

int availableForWrite ( )

inlineoverridevirtual

Reimplemented from BaseStream.

begin() [1/2]

bool begin ( )

inlinevirtual

Initialization of ESPNow.

Reimplemented from BaseStream.

begin() [2/2]

virtual bool begin ( ESPNowStreamConfig cfg )

inlinevirtual

Initialization of ESPNow incl WIFI.

bufferAvailableForWrite()

int bufferAvailableForWrite ( )

inlinestaticprotected

clearPeers()

bool clearPeers ( )

inline

Deletes all registered peers.

default_recv_cb()

void default_recv_cb ( const esp_now_recv_info * info, const uint8_t * data, int data_len )

inlinestaticprotected

default_send_cb()

void default_send_cb ( const wifi_tx_info_t * tx_info, esp_now_send_status_t status )

inlinestaticprotected

defaultConfig()

ESPNowStreamConfig defaultConfig ( )

inline

end()

virtual void end ( )

inlinevirtual

DeInitialization.

Reimplemented from BaseStream.

flush() [1/2]

virtual void flush ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in AudioStreamWrapper, AudioStreamWrapper, BufferedStream, BufferedStream, EncodedAudioStream, FilteredStream< T, TF >, FilteredStream< T, TF >, FilteredStream< int16_t, int16_t >, GeneratedSoundStream< T >, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, MemoryStream, MemoryStream, QueueStream< T >, QueueStream< T >, QueueStream< uint8_t >, ReformatBaseStream, RingBufferStream, RingBufferStream, TimedStream, AudioEffectStream, AudioEffectStreamT< T >, AudioStreamWrapper, AutomaticGainControlStream, BufferedStream, BufferedTaskStream, EncodedAudioStream, Equalizer3BandsPerChannelT< T >, Equalizer3BandsPerChannelT< float >, Equalizer3BandsT< T >, Equalizer3BandsT< float >, EqualizerNBands< SampleT, AccT, NUM_TAPS, NUM_BANDS >, FadeStream, FilteredStream< T, TF >, GeneratedSoundStream< T >, I2SStream, MeasuringStream, MemoryStream, Pipeline::ModifyingStreamAdapter, PureDataStream, QualityAnalysisStream, QueueStream< T >, ReformatBaseStream, ResampleStream, RingBufferStream, SupportedRatesStream, TimedStream, URLStream, URLStreamBufferedT< T >, URLStreamBufferedT< ICYStream >, URLStreamBufferedT< ICYStreamESP32 >, URLStreamBufferedT< URLStream >, URLStreamBufferedT< URLStreamESP32 >, and VolumeStream.

flush() [2/2]

virtual void flush ( )

inlineoverridevirtualinherited

Reimplemented from Print.

Reimplemented in AudioStreamWrapper, AudioStreamWrapper, BufferedStream, BufferedStream, EncodedAudioStream, FilteredStream< T, TF >, FilteredStream< T, TF >, FilteredStream< int16_t, int16_t >, GeneratedSoundStream< T >, GeneratedSoundStream< T >, GeneratedSoundStream< int16_t >, MemoryStream, MemoryStream, QueueStream< T >, QueueStream< T >, QueueStream< uint8_t >, ReformatBaseStream, RingBufferStream, RingBufferStream, TimedStream, AudioEffectStream, AudioEffectStreamT< T >, AudioStreamWrapper, AutomaticGainControlStream, BufferedStream, BufferedTaskStream, EncodedAudioStream, Equalizer3BandsPerChannelT< T >, Equalizer3BandsPerChannelT< float >, Equalizer3BandsT< T >, Equalizer3BandsT< float >, EqualizerNBands< SampleT, AccT, NUM_TAPS, NUM_BANDS >, FadeStream, FilteredStream< T, TF >, GeneratedSoundStream< T >, I2SStream, MeasuringStream, MemoryStream, Pipeline::ModifyingStreamAdapter, PureDataStream, QualityAnalysisStream, QueueStream< T >, ReformatBaseStream, ResampleStream, RingBufferStream, SupportedRatesStream, TimedStream, URLStream, URLStreamBufferedT< T >, URLStreamBufferedT< ICYStream >, URLStreamBufferedT< ICYStreamESP32 >, URLStreamBufferedT< URLStream >, URLStreamBufferedT< URLStreamESP32 >, and VolumeStream.

getBuffer()

BufferRTOS< uint8_t > & getBuffer ( )

inline

provides access to the receive buffer

getBufferPercent()

float getBufferPercent ( )

inline

provides how much the receive buffer is filled (in percent)

getChannel()

uint8_t getChannel ( )

inline

Provides the WiFi Channel.

getInterface()

wifi_interface_t getInterface ( )

inlineprotected

getLastIoSuccessTime()

uint32_t getLastIoSuccessTime ( ) const

inline

time when we were able to send or receive the last packet successfully

handle_recv_cb()

virtual void handle_recv_cb ( const uint8_t * mac_addr, const uint8_t * data, int data_len, bool broadcast, uint8_t rssi )

inlineprotectedvirtual

handle_send_cb()

virtual void handle_send_cb ( const uint8_t * mac_addr, esp_now_send_status_t status )

inlineprotectedvirtual

handleQueueError()

bool handleQueueError ( esp_err_t rc, int & retry_count )

inlineprotected

Handles errors when queuing packets.

handleTransmissionResult()

bool handleTransmissionResult ( int & retry_count )

inlineprotected

Handles the result of packet transmission (after queuing).

initWiFi()

bool initWiFi ( wifi_mode_t mode )

inlineprotected

isEncrypted()

bool isEncrypted ( )

inlineprotected

mac2str()

const char * mac2str ( const uint8_t * array )

inlineprotected

macAddress()

const char * macAddress ( )

inline

Returns the mac address of the current ESP32.

operator bool() [1/2]

operator bool ( )

inlineinherited

operator bool() [2/2]

operator bool ( )

inlineinherited

readBytes()

size_t readBytes ( uint8_t * data, size_t len )

inlineoverridevirtual

Reeds the data from the peers.

Implements BaseStream.

refillReadBuffer() [1/2]

void refillReadBuffer ( )

inlineprotectedinherited

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

refillReadBuffer() [2/2]

void refillReadBuffer ( )

inlineprotectedinherited

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

resetAvailableToWrite()

void resetAvailableToWrite ( )

inlineprotected

sendPacket()

virtual bool sendPacket ( const uint8_t * data, size_t len, int & retry_count, const uint8_t * destination = nullptr )

inlineprotectedvirtual

Sends a single packet with retry logic.

setChannel()

void setChannel ( uint8_t ch )

inline

Defines the WiFi Channel.

setReceiveCallback()

void setReceiveCallback ( esp_now_recv_cb_t cb )

inline

Defines the Receive Callback - Deactivates the readBytes and available() methods!

setSendCallback()

void setSendCallback ( esp_now_send_cb_t cb )

inline

Defines an alternative send callback.

setup()

bool setup ( )

inlineprotected

Initialization.

setupMAC()

bool setupMAC ( )

inlineprotected

setupReceiveBuffer()

void setupReceiveBuffer ( )

inlineprotected

setupSemaphore()

void setupSemaphore ( )

inlineprotected

setupWiFi()

bool setupWiFi ( )

inlineprotected

setWriteBufferSize() [1/2]

void setWriteBufferSize ( int size )

inlineinherited

setWriteBufferSize() [2/2]

void setWriteBufferSize ( int size )

inlineinherited

str2mac()

bool str2mac ( const char * mac, uint8_t * values )

inlineprotected

write() [1/4]

virtual size_t write ( uint8_t ch )

inlineoverridevirtualinherited

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

write() [2/4]

size_t write ( const char * peer, const uint8_t * data, size_t len )

inline

Writes the data - sends it to all the indicated peer mac address string.

write() [3/4]

size_t write ( const uint8_t * data, size_t len )

inlineoverridevirtual

Writes the data - sends it to all registered peers.

Implements BaseStream.

write() [4/4]

size_t write ( const uint8_t * peer, const uint8_t * data, size_t len )

inline

Writes the data - sends it to all the peers.

Member Data Documentation

_timeout

int _timeout = 10

protectedinherited

available_to_write

volatile size_t available_to_write = 0

protected

buffer

BufferRTOS<uint8_t> buffer {0}

protected

cfg

ESPNowStreamConfig cfg

protected

has_peers

bool has_peers = false

protected

is_broadcast

bool is_broadcast = false

protected

is_init

bool is_init = false

protected

last_io_success_time

uint32_t last_io_success_time = 0

protected

last_send_success

volatile bool last_send_success = true

protected

read_ready

bool read_ready = false

protected

receive

esp_now_recv_cb_t receive = default_recv_cb

protected

send

esp_now_send_cb_t send = default_send_cb

protected

tmp_in

RingBuffer< uint8_t > tmp_in {0}

protectedinherited

tmp_out

RingBuffer< uint8_t > tmp_out {0}

protectedinherited

write_buffer_size

int write_buffer_size = 8

protectedinherited

xSemaphore

SemaphoreHandle_t xSemaphore = nullptr

protected

---

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

• src/AudioTools/Communication/ESPNowStream.h