Class WiFiUdp

WiFiUDP Class

Description

A class used for managing WiFi UDP implementation for Ameba.

Syntax

class WiFiUDP

Members

Public Constructors
WiFiUDP::WiFiUDP	Constructs a WiFiUDP instance of the Wi-Fi UDP class that can send and receive UDP messages.
Public Methods
WiFiUDP::begin	Initialize Wi-Fi UDP library, network settings and start listening at specified local port.
WiFiUDP::stop	Disconnect from the server.
WiFiUDP::beginPacket	Start building up a packet to send to the remote host-specific in IP and port.
WiFiUDP::endPacket	Finish off this packet and send it.
WiFiUDP::write	Write UDP data (single byte) to remote connection.
WiFiUDP::writeImmediately	Send packet immediately from the buffer.
WiFiUDP::parsePacket	Check for the presence of a UDP packets and start processing the next available incoming packet.
WiFiUDP::available	Get the number of bytes (characters) available for reading from the buffer.
WiFiUDP::read	Read UDP data from specified buffer.
WiFiUDP::peek	Get the next byte from the current packet without moving on to the next byte.
WiFiUDP::flush	Clear all the bytes that have been written to the client but not yet read.
WiFiUDP::remoteIP	Get the IP address of the remote connection who sent the current incoming packet.
WiFiUDP::remotePort	Get the port of the remote UDP connection who sent the current incoming packet.
WiFiUDP::setRecvTimeout	Set receiving timeout.

WiFiUDP::WiFiUDP

Description

Constructs a WiFiUDP instance of the Wi-Fi UDP class that can send and receive UDP messages.

Syntax

WiFiUDP (void);

Example Code

Example: WiFiUdpSendReceiveString

Note

This constructor does not take in any parameter, thus use another method to set up the IP address and port number. “WiFiUdp.h” must be included to use the class function.

WiFiUDP::begin

Description

Initialize Wi-Fi UDP library, network settings and start listening at specified local port.

Syntax

virtual uint8_t begin(uint16_t);

Returns

This function returns 1 if successful, else returns 0 if there are no sockets available to use.

Example Code

Example: WiFiUdpSendReceiveString

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::stop

Description

Disconnect from the server. Release any resource being used during the UDP session.

Syntax

virtual void stop(void);

Example Code

NA

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::beginPacket

Description

Start building up a packet to send to the remote host-specific in IP and port.

Syntax

virtual int beginPacket(IPAddress ip, uint16_t port);
virtual int beginPacket(const char *host, uint16_t port);

Parameters

host: remote host name.

port: the port of the remote connection.

ip: IP address of the remote connection.

Returns

This function returns “1” of successful, else returns “0” if there is a problem with the given IP address or port.

Example Code

Example: WiFiUdpSendReceiveString

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::endPacket

Syntax

virtual int endPacket(void);

Returns

This function returns “1” if packet was sent successfully, else returns “0” if there was an error.

Example Code

Example: WiFiUdpSendReceiveString

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::write

Description

Write UDP data (single byte) to remote connection.

Syntax

virtual size_t write(uint8_t);
virtual size_t write(const uint8_t *buffer, size_t size);

Parameters

buf: a pointer to an array containing the outgoing message.

size: the size of the buffer.

Returns

This function returns the byte / character that will be written to the server or the size of the buffer.

This function must be wrapped between beginPacket() and endPacket(). beginPacket() initializes the packet of data, it is not sent until endPacket() is called. “WiFiUdp.h” must be included to use the class function.

WiFiUDP::writeImmediately

Description

Send packet immediately from the buffer.

Syntax

int writeImmediately(const uint8_t *buffer, size_t size);
int writeImmediately(const uint8_t *buffer, size_t size, uint32_t peer_ip, uint16_t peer_port);

Parameters

*buffer: a pointer to an array containing the outgoing message.

size: the size of the buffer.

peer_ip: ip address of peer device

peer_port: port number of peer device

Returns

This function returns the byte / character that will be written to the server or the size of the buffer.

Example Code

NA

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::parsePacket

Description

Check for the presence of a UDP packets and start processing the next available incoming packet.

Syntax

int parsePacket(void);

Parameters

NA

Returns

This function returns the number of bytes available in the current packet, will return “0” if WiFiUDP.parsePacket() hasn’t been called yet.

Example Code

Example: WiFiUdpSendReceiveString

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::available

Description

Get the number of bytes (characters) available for reading from the buffer.

Syntax

virtual int available(void);

Parameters

NA

Returns

This function returns the number of bytes available in the current packet, else returns “0” if WiFiUDP.parsePacket() hasn’t been called yet.

Example Code

NA

Note

This function can only be successfully called after WiFiUDP.parsePacket(). “WiFiUdp.h” must be included to use the class function.

WiFiUDP::read

Description

Read UDP data from specified buffer.

Syntax

virtual int read (void);
virtual int read (char *buffer, size_t len);

Parameters

buf: buffer to hold incoming byte.

size: maximum size of the buffer.

Returns

This function returns the size of the buffer or returns -1 if no buffer is available.

Example Code

Example: WiFiUdpSendReceiveString

Note

This function can only be successfully called after WiFiUDP.parsePacket(). “WiFiUdp.h” must be included to use the class function.

WiFiUDP::peek

Description

Get the next byte from the current packet without moving on to the next byte.

Syntax

virtual int peek (void);

Parameters

NA

Returns

This function returns the next byte or character or returns -1 if none is available.

Example Code

NA

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::flush

Description

Clear all the bytes that have been written to the client but not yet read.

Syntax

virtual void flush(void);

Parameters

NA

Returns

NA

Example Code

NA

Note

“WiFiUdp.h” must be included to use the class function.

WiFiUDP::remoteIP

Description

Get the IP address of the remote connection who sent the current incoming packet.

Syntax

virtual IPAddress remoteIP(void);

Parameters

NA

Returns

This function returns the IP address of the remote connection.

Example Code

Example: WiFiUdpSendReceiveString

Note

This function must be called after WiFiUDP.parsePacket(). “WiFiUdp.h” must be included to use the class function.

virtual uint16_t remotePort(void);

This function must be called after WiFiUDP.parsePacket(). “WiFiUdp.h” must be included to use the class function.

void setRecvTimeout(int timeout);

“WiFiUdp.h” must be included to use the class function.