HRFDatagram Class Reference

Class for addressed, unreliable messages. More...

#include <HRFDatagram.h>

Inheritance diagram for HRFDatagram:

List of all members.

Public Member Functions
	HRFDatagram (HardwareSerial *serial=&Serial, uint8_t thisAddress=0)
virtual void	setThisAddress (uint8_t thisAddress)
virtual uint8_t	sendto (uint8_t address, uint8_t *buf, uint8_t len)
virtual uint8_t	recvfrom (uint8_t *buf, uint8_t *len, uint8_t *from=NULL, uint8_t *to=NULL, uint8_t promiscuous=0)
virtual uint8_t	recv (uint8_t *buf, uint8_t *len)
Protected Attributes
uint8_t	_thisAddress
	The address of this node. Defaults to 0.

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Detailed Description

Class for addressed, unreliable messages.

Extends HRFMessage to define addressed, unreliable datagrams. Every node has an 8 bit address (defaults to 0). Datagrams have format LEN DEST SRC payload FCS-LO FCS-HI. Addresses (DEST and SRC) are 8 bit integers with an address of HRF_BROADCAST_ADDRESS (0xff) reserved for broadcast.

Part of the Arduino HopeRF library for operating with HopeRF HM-TR transceivers (see http://www.hoperf.com).

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Constructor & Destructor Documentation

HRFDatagram::HRFDatagram	(	HardwareSerial *	serial = &Serial,
		uint8_t	thisAddress = 0
	)

Parameters:

[in]	serial	The instance of HardwareSerial to use for IO. Defaults to &Serial,
[in]	thisAddress	The address to assign to this node. Defaults to 0

References setThisAddress().

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Member Function Documentation

void HRFDatagram::setThisAddress

(

uint8_t

thisAddress

)

[virtual]

Sets the address of this node. Defaults to 0. If all the nodes leave the address unset (ie 0), HRFDatagram acts much the same as HRFMessage (with a bit more overhead). In a conventional multinode system, all nodes will have a unique address (which you could store in EEPROM). However, if you only have 2 nodes in the network, you can leave the addresses of each set to the default of 0.

Parameters:

[in]

thisAddress

The address of this node

References _thisAddress.

Referenced by HRFDatagram().

uint8_t HRFDatagram::sendto	(	uint8_t	address,
		uint8_t *	buf,
		uint8_t	len
	)			[virtual]

Sends a message to the node(s) with the given address HRF_BROADCAST_ADDRESS is a valid address which will cause the message to be accepted by all HRFDatagram nodes within range.

Parameters:

[in]	address	The address to send the message to.
[in]	buf	Pointer to the binary message to send
[in]	len	Number of octets to send

Returns:

true if the message was transmitted.

false if the message is too long (>HRF_MAX_DATAGRAM_PAYLOAD).

References _thisAddress, and HRFMessage::send().

Referenced by HRFReliableDatagram::recvfromAck(), and HRFReliableDatagram::sendtoWait().

uint8_t HRFDatagram::recvfrom	(	uint8_t *	buf,
		uint8_t *	len,
		uint8_t *	from = NULL,
		uint8_t *	to = NULL,
		uint8_t	promiscuous = 0
	)			[virtual]

If there is a message available for this node, copy it to buf and return true If the message was valid (ie good FCS), return true else return false. The SRC address is placed in *from if present and not NULL. The DEST address is placed in *to if present and not NULL. If promiscuous is present and true, all messages will be returned, not just those addressed to this node. If a message is copied, *len is set to the length.

Parameters:

[in]	buf	Location to copy the received message
[in]	len	Available space in buf. Set to the actual number of octets copied.
[in]	from	If present and not NULL, the referenced uint8_t will be set to the SRC address
[in]	to	If present and not NULL, the referenced uint8_t will be set to the DEST address
[in]	promiscuous	If present and true, return all received messages (not just those addressed to this node).

Returns:

true if a valid (good FCS) message was copied to buf

References _thisAddress, and HRFMessage::recv().

Referenced by recv(), HRFReliableDatagram::recvfromAck(), and HRFReliableDatagram::sendtoWait().

uint8_t HRFDatagram::recv	(	uint8_t *	buf,
		uint8_t *	len
	)			[virtual]

If there is a valid message available for this node, copy it to buf and return true else return false. You can't recover the SRC or DEST address with this call, so you would only use it if you do not intend to reply. If a message is copied, *len is set to the length.

Parameters:

[in]	buf	Location to copy the received message
[in]	len	Available space in buf. Set to the actual number of octets copied.

Returns:

true if a valid message was copied to buf

Reimplemented from HRFMessage.

References recvfrom().

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

• HRFDatagram.h
• HRFDatagram.cpp