A protocol that handles the NMEA 2000 fast packet protocol. More...

#include <nmea2000_fast_packet_protocol.hpp>

Classes
struct	FastPacketHistory
	A structure for keeping track of past sessions so we can resume with the right session number. More...

class	FastPacketProtocolSession
	An object for tracking fast packet session state. More...

Public Member Functions
	FastPacketProtocol (const CANMessageFrameCallback &sendCANFrameCallback)
	The constructor for the FastPacketProtocol, for advanced use only. In most cases, you should use the CANNetworkManager::get_fast_packet_protocol().send_message() function to transmit messages.

void	register_multipacket_message_callback (std::uint32_t parameterGroupNumber, CANLibCallback callback, void *parent, std::shared_ptr< InternalControlFunction > internalControlFunction=nullptr)
	Add a callback to be called when a message is received by the Fast Packet protocol.

void	remove_multipacket_message_callback (std::uint32_t parameterGroupNumber, CANLibCallback callback, void *parent, std::shared_ptr< InternalControlFunction > internalControlFunction=nullptr)

bool	send_multipacket_message (std::uint32_t parameterGroupNumber, const std::uint8_t data, std::uint8_t messageLength, std::shared_ptr< InternalControlFunction > source, std::shared_ptr< ControlFunction > destination, CANIdentifier::CANPriority priority=CANIdentifier::CANPriority::PriorityDefault6, TransmitCompleteCallback txCompleteCallback=nullptr, void parentPointer=nullptr, DataChunkCallback frameChunkCallback=nullptr)
	Used to send CAN messages using fast packet.

void	allow_any_control_function (bool allow)
	Set whether or not to allow messages for non-internal control functions to be parsed by this protocol.

void	update ()
	Updates all sessions managed by this protocol manager instance.

void	process_message (const CANMessage &message)
	A generic way for a protocol to process a received message.

Static Public Member Functions
static std::uint8_t	calculate_number_of_frames (std::uint8_t messageLength)
	Calculates the number of frames needed for a message.

Private Member Functions
void	add_session_history (const std::shared_ptr< FastPacketProtocolSession > &session)
	Adds a session's info to the history so that we can continue the sequence number later.

void	close_session (std::shared_ptr< FastPacketProtocolSession > session, bool successful)
	Gracefully closes a session to prepare for a new session.

std::uint8_t	get_new_sequence_number (NAME name, std::uint32_t parameterGroupNumber) const
	Get the sequence number to use for a new session based on the history of past sessions.

std::shared_ptr< FastPacketProtocolSession >	get_session (std::uint32_t parameterGroupNumber, std::shared_ptr< ControlFunction > source, std::shared_ptr< ControlFunction > destination)
	Gets a FP session from the passed in source and destination and PGN combination.

bool	has_session (std::uint32_t parameterGroupNumber, std::shared_ptr< ControlFunction > source, std::shared_ptr< ControlFunction > destination)
	Checks if a session by the passed in source and destination and PGN combination exists.

void	update_session (const std::shared_ptr< FastPacketProtocolSession > &session)
	Update a single session.

Private Attributes
std::vector< std::shared_ptr< FastPacketProtocolSession > >	activeSessions
	A list of all active TP sessions.

Mutex	sessionMutex
	A mutex to lock the sessions list in case someone starts a Tx while the stack is processing sessions.

std::vector< FastPacketHistory >	sessionHistory
	Used to keep track of sequence numbers for future sessions.

std::vector< ParameterGroupNumberCallbackData >	parameterGroupNumberCallbacks
	A list of all parameter group number callbacks that will be parsed as fast packet messages.

bool	allowAnyControlFunction = false
	Denotes if messages for non-internal control functions should be parsed by this protocol.

const CANMessageFrameCallback	sendCANFrameCallback
	A callback for sending a CAN frame.

Static Private Attributes
static constexpr std::uint32_t	FP_MIN_PARAMETER_GROUP_NUMBER = 0x1F000
	Start of PGNs that can be received via Fast Packet.

static constexpr std::uint32_t	FP_MAX_PARAMETER_GROUP_NUMBER = 0x1FFFF
	End of PGNs that can be received via Fast Packet.

static constexpr std::uint32_t	FP_TIMEOUT_MS = 750
	Protocol timeout in milliseconds.

static constexpr std::uint8_t	MAX_PROTOCOL_MESSAGE_LENGTH = 223
	Max message length based on there being 5 bits of sequence data.

static constexpr std::uint8_t	FRAME_COUNTER_BIT_MASK = 0x1F
	Bit mask for masking out the frame counter.

static constexpr std::uint8_t	SEQUENCE_NUMBER_BIT_MASK = 0x07
	Bit mask for masking out the sequence number bits.

static constexpr std::uint8_t	SEQUENCE_NUMBER_BIT_OFFSET = 5
	The bit offset into the first byte of data to get the seq number.

static constexpr std::uint8_t	PROTOCOL_BYTES_PER_FRAME = 7
	The number of payload bytes per frame for all but the first message, which has 6.

Detailed Description

A protocol that handles the NMEA 2000 fast packet protocol.

Definition at line 37 of file nmea2000_fast_packet_protocol.hpp.

Constructor & Destructor Documentation

◆ FastPacketProtocol()

isobus::FastPacketProtocol::FastPacketProtocol ( const CANMessageFrameCallback & sendCANFrameCallback )

explicit

The constructor for the FastPacketProtocol, for advanced use only. In most cases, you should use the CANNetworkManager::get_fast_packet_protocol().send_message() function to transmit messages.

Parameters

[in] sendCANFrameCallback A callback for sending a CAN frame to hardware

Definition at line 105 of file nmea2000_fast_packet_protocol.cpp.

Member Function Documentation

◆ add_session_history()

void isobus::FastPacketProtocol::add_session_history ( const std::shared_ptr< FastPacketProtocolSession > & session )

private

Adds a session's info to the history so that we can continue the sequence number later.

Parameters

[in] session The session to add to the history

Definition at line 211 of file nmea2000_fast_packet_protocol.cpp.

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◆ allow_any_control_function()

void isobus::FastPacketProtocol::allow_any_control_function ( bool allow )

Set whether or not to allow messages for non-internal control functions to be parsed by this protocol.

Parameters

[in] allow Denotes if messages for non-internal control functions should be parsed by this protocol

Definition at line 125 of file nmea2000_fast_packet_protocol.cpp.

◆ calculate_number_of_frames()

std::uint8_t isobus::FastPacketProtocol::calculate_number_of_frames ( std::uint8_t messageLength )

static

Calculates the number of frames needed for a message.

Parameters

[in] messageLength The length of the message in bytes

Returns: The number of frames needed for the message

Definition at line 88 of file nmea2000_fast_packet_protocol.cpp.

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◆ close_session()

void isobus::FastPacketProtocol::close_session	(	std::shared_ptr< FastPacketProtocolSession >	session,
		bool	successful )

private

Gracefully closes a session to prepare for a new session.

Parameters

[in]	session	The session to close
[in]	successful	Denotes if the session was successful

Definition at line 240 of file nmea2000_fast_packet_protocol.cpp.

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◆ get_new_sequence_number()

std::uint8_t isobus::FastPacketProtocol::get_new_sequence_number	(	NAME	name,
		std::uint32_t	parameterGroupNumber ) const

private

Get the sequence number to use for a new session based on the history of past sessions.

Parameters

[in]	name	The ISO name of the internal control function used in a session
[in]	parameterGroupNumber	The PGN of the session being started

Returns: The sequence number to use for the new session

Definition at line 255 of file nmea2000_fast_packet_protocol.cpp.

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◆ get_session()

std::shared_ptr< FastPacketProtocol::FastPacketProtocolSession > isobus::FastPacketProtocol::get_session	(	std::uint32_t	parameterGroupNumber,
		std::shared_ptr< ControlFunction >	source,
		std::shared_ptr< ControlFunction >	destination )

private

Gets a FP session from the passed in source and destination and PGN combination.

Parameters

[in]	parameterGroupNumber	The PGN of the session
[in]	source	The source control function for the session
[in]	destination	The destination control function for the session

Returns: a matching session, or nullptr if no session matched the supplied parameters

Definition at line 502 of file nmea2000_fast_packet_protocol.cpp.

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◆ has_session()

bool isobus::FastPacketProtocol::has_session	(	std::uint32_t	parameterGroupNumber,
		std::shared_ptr< ControlFunction >	source,
		std::shared_ptr< ControlFunction >	destination )

private

Checks if a session by the passed in source and destination and PGN combination exists.

Parameters

[in]	parameterGroupNumber	The PGN of the session
[in]	source	The source control function for the session
[in]	destination	The destination control function for the session

Returns: true if a matching session exists, false if not

Definition at line 494 of file nmea2000_fast_packet_protocol.cpp.

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◆ process_message()

void isobus::FastPacketProtocol::process_message ( const CANMessage & message )

A generic way for a protocol to process a received message.

Parameters

[in] message A received CAN message

Definition at line 269 of file nmea2000_fast_packet_protocol.cpp.

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◆ register_multipacket_message_callback()

void isobus::FastPacketProtocol::register_multipacket_message_callback	(	std::uint32_t	parameterGroupNumber,
		CANLibCallback	callback,
		void *	parent,
		std::shared_ptr< InternalControlFunction >	internalControlFunction = nullptr )

Add a callback to be called when a message is received by the Fast Packet protocol.

Parameters

[in]	parameterGroupNumber	The PGN to parse as fast packet
[in]	callback	The callback that the stack will call when a matching message is received
[in]	parent	Generic context variable for the callback
[in]	internalControlFunction	An internal control function to use as an additional filter for the callback. Only messages destined for the specified ICF will generate a callback. Use nullptr to receive messages for destined for any ICF and broadcast messages.

Note: You can also sniff all messages by allowing messages for messages destined to non-internal control functions to be parsed by this protocol, use the "allow_any_control_function()" function to enable this.

Definition at line 110 of file nmea2000_fast_packet_protocol.cpp.

◆ remove_multipacket_message_callback()

void isobus::FastPacketProtocol::remove_multipacket_message_callback	(	std::uint32_t	parameterGroupNumber,
		CANLibCallback	callback,
		void *	parent,
		std::shared_ptr< InternalControlFunction >	internalControlFunction = nullptr )

Parameters

[in]	parameterGroupNumber	The PGN to parse as fast packet
[in]	callback	The callback that the stack will call when a matching message is received
[in]	parent	Generic context variable
[in]	internalControlFunction	An internal control function used as an additional filter for the callback

Definition at line 115 of file nmea2000_fast_packet_protocol.cpp.

◆ send_multipacket_message()

bool isobus::FastPacketProtocol::send_multipacket_message	(	std::uint32_t	parameterGroupNumber,
		const std::uint8_t *	data,
		std::uint8_t	messageLength,
		std::shared_ptr< InternalControlFunction >	source,
		std::shared_ptr< ControlFunction >	destination,
		CANIdentifier::CANPriority	priority = CANIdentifier::CANPriority::PriorityDefault6,
		TransmitCompleteCallback	txCompleteCallback = nullptr,
		void *	parentPointer = nullptr,
		DataChunkCallback	frameChunkCallback = nullptr )

Used to send CAN messages using fast packet.

You have to use this function instead of the network manager because otherwise the CAN stack has no way of knowing to send your message with FP instead of TP.

Parameters

[in]	parameterGroupNumber	The PGN of the message
[in]	data	The data to be sent
[in]	messageLength	The length of the data to be sent
[in]	source	The source control function
[in]	destination	The destination control function
[in]	priority	The priority to encode in the IDs of the component CAN messages
[in]	txCompleteCallback	A callback for when the protocol completes its work
[in]	parentPointer	A generic context object for the tx complete and chunk callbacks
[in]	frameChunkCallback	A callback to get some data to send

Returns: true if the message was accepted by the protocol for processing

Definition at line 130 of file nmea2000_fast_packet_protocol.cpp.

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◆ update()

void isobus::FastPacketProtocol::update ( )

Updates all sessions managed by this protocol manager instance.

Definition at line 190 of file nmea2000_fast_packet_protocol.cpp.

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◆ update_session()

void isobus::FastPacketProtocol::update_session ( const std::shared_ptr< FastPacketProtocolSession > & session )

private

Update a single session.

Parameters

[in] session The session to update

Definition at line 420 of file nmea2000_fast_packet_protocol.cpp.

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Member Data Documentation

◆ activeSessions

std::vector<std::shared_ptr<FastPacketProtocolSession> > isobus::FastPacketProtocol::activeSessions

private

A list of all active TP sessions.

Definition at line 219 of file nmea2000_fast_packet_protocol.hpp.

◆ allowAnyControlFunction

bool isobus::FastPacketProtocol::allowAnyControlFunction = false

private

Denotes if messages for non-internal control functions should be parsed by this protocol.

Definition at line 223 of file nmea2000_fast_packet_protocol.hpp.

◆ FP_MAX_PARAMETER_GROUP_NUMBER

constexpr std::uint32_t isobus::FastPacketProtocol::FP_MAX_PARAMETER_GROUP_NUMBER = 0x1FFFF

staticconstexprprivate

End of PGNs that can be received via Fast Packet.

Definition at line 211 of file nmea2000_fast_packet_protocol.hpp.

◆ FP_MIN_PARAMETER_GROUP_NUMBER

constexpr std::uint32_t isobus::FastPacketProtocol::FP_MIN_PARAMETER_GROUP_NUMBER = 0x1F000

staticconstexprprivate

Start of PGNs that can be received via Fast Packet.

Definition at line 210 of file nmea2000_fast_packet_protocol.hpp.

◆ FP_TIMEOUT_MS

constexpr std::uint32_t isobus::FastPacketProtocol::FP_TIMEOUT_MS = 750

staticconstexprprivate

Protocol timeout in milliseconds.

Definition at line 212 of file nmea2000_fast_packet_protocol.hpp.

◆ FRAME_COUNTER_BIT_MASK

constexpr std::uint8_t isobus::FastPacketProtocol::FRAME_COUNTER_BIT_MASK = 0x1F

staticconstexprprivate

Bit mask for masking out the frame counter.

Definition at line 214 of file nmea2000_fast_packet_protocol.hpp.

◆ MAX_PROTOCOL_MESSAGE_LENGTH

constexpr std::uint8_t isobus::FastPacketProtocol::MAX_PROTOCOL_MESSAGE_LENGTH = 223

staticconstexprprivate

Max message length based on there being 5 bits of sequence data.

Definition at line 213 of file nmea2000_fast_packet_protocol.hpp.

◆ parameterGroupNumberCallbacks

std::vector<ParameterGroupNumberCallbackData> isobus::FastPacketProtocol::parameterGroupNumberCallbacks

private

A list of all parameter group number callbacks that will be parsed as fast packet messages.

Definition at line 222 of file nmea2000_fast_packet_protocol.hpp.

◆ PROTOCOL_BYTES_PER_FRAME

constexpr std::uint8_t isobus::FastPacketProtocol::PROTOCOL_BYTES_PER_FRAME = 7

staticconstexprprivate

The number of payload bytes per frame for all but the first message, which has 6.

Definition at line 217 of file nmea2000_fast_packet_protocol.hpp.

◆ sendCANFrameCallback

const CANMessageFrameCallback isobus::FastPacketProtocol::sendCANFrameCallback

private

A callback for sending a CAN frame.

Definition at line 224 of file nmea2000_fast_packet_protocol.hpp.

◆ SEQUENCE_NUMBER_BIT_MASK

constexpr std::uint8_t isobus::FastPacketProtocol::SEQUENCE_NUMBER_BIT_MASK = 0x07

staticconstexprprivate

Bit mask for masking out the sequence number bits.

Definition at line 215 of file nmea2000_fast_packet_protocol.hpp.

◆ SEQUENCE_NUMBER_BIT_OFFSET

constexpr std::uint8_t isobus::FastPacketProtocol::SEQUENCE_NUMBER_BIT_OFFSET = 5

staticconstexprprivate

The bit offset into the first byte of data to get the seq number.

Definition at line 216 of file nmea2000_fast_packet_protocol.hpp.

◆ sessionHistory

std::vector<FastPacketHistory> isobus::FastPacketProtocol::sessionHistory

private

Used to keep track of sequence numbers for future sessions.

Definition at line 221 of file nmea2000_fast_packet_protocol.hpp.

◆ sessionMutex

Mutex isobus::FastPacketProtocol::sessionMutex

private

A mutex to lock the sessions list in case someone starts a Tx while the stack is processing sessions.

Definition at line 220 of file nmea2000_fast_packet_protocol.hpp.

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

isobus/include/isobus/isobus/nmea2000_fast_packet_protocol.hpp
isobus/src/nmea2000_fast_packet_protocol.cpp

Classes

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ FastPacketProtocol()

Member Function Documentation

◆ add_session_history()

◆ allow_any_control_function()

◆ calculate_number_of_frames()

◆ close_session()

◆ get_new_sequence_number()

◆ get_session()

◆ has_session()

◆ process_message()

◆ register_multipacket_message_callback()

◆ remove_multipacket_message_callback()

◆ send_multipacket_message()

◆ update()

◆ update_session()

Member Data Documentation

◆ activeSessions

◆ allowAnyControlFunction

◆ FP_MAX_PARAMETER_GROUP_NUMBER

◆ FP_MIN_PARAMETER_GROUP_NUMBER

◆ FP_TIMEOUT_MS

◆ FRAME_COUNTER_BIT_MASK

◆ MAX_PROTOCOL_MESSAGE_LENGTH

◆ parameterGroupNumberCallbacks

◆ PROTOCOL_BYTES_PER_FRAME

◆ sendCANFrameCallback

◆ SEQUENCE_NUMBER_BIT_MASK

◆ SEQUENCE_NUMBER_BIT_OFFSET

◆ sessionHistory

◆ sessionMutex