Implements an interface against a CAN Data Frame message. More...

#include "bus/candataframe.h"

Inheritance diagram for bus::CanDataFrame:

Collaboration diagram for bus::CanDataFrame:

Public Member Functions
	CanDataFrame ()
	Deafult constructor.
	CanDataFrame (CanErrorType type)=delete
	CanDataFrame (const std::shared_ptr< IBusMessage > &message)
	Create a message from a raw byte array.
void	MessageId (uint32_t msg_id)
	DBC message ID. Note that bit 31 indicate extended ID.
uint32_t	MessageId () const
	DBC message ID. Note that bit 31 indicate extended ID.
void	CanId (uint32_t can_id)
	Returns the 11/27 bit CAN ID.
uint32_t	CanId () const
	29/11 bit CAN message ID. Note that bit 31 is not used.
void	ExtendedId (bool extended)
	Set true if the CAN ID uses 20-bit addressing.
bool	ExtendedId () const
	Returns true if the CAN ID uses 29-bit addressing,.
void	Dlc (uint8_t dlc)
	Sets the CAN message data length code.
uint8_t	Dlc () const
	Returns the data length code (DLC).
void	Crc (uint32_t crc)
	Sets the CRC code.
uint32_t	Crc () const
	Returns the CRC code.
void	DataLength (uint8_t data_length)
	Sets number of data bytes.
uint8_t	DataLength () const
	Returns number of data bytes.
void	DataBytes (const std::vector< uint8_t > &data)
	Sets the payload data bytes.
const std::vector< uint8_t > &	DataBytes () const
	Returns a reference to the payload data bytes.
void	Dir (bool transmit)
	If set true, the message was transmitted.
bool	Dir () const
	Returns true if the message was transmitted.
void	Srr (bool srr)
	Sets the SRR bit. *‍/.
bool	Srr () const
	Returns the SRR bit.
void	Edl (bool edl)
	Extended (CAN FD) data length.
bool	Edl () const
	Extended (CAN FD) data length.
void	Brs (bool brs)
	Bit rate switch (CAN FD).
bool	Brs () const
	Bit rate switch (CAN FD).
void	Esi (bool esi)
	Error state indicator (CAN FD).
bool	Esi () const
	Error state indicator (CAN FD).
void	Rtr (bool rtr)
	Sets the RTR bit (remote frame).
bool	Rtr () const
	Returns the RTR bit.
void	WakeUp (bool wake_up)
	Indicate a CAN bus wake up status.
bool	WakeUp () const
	Indicate a CAN bus wake up message.
void	SingleWire (bool single_wire)
	Indicate a single wire CAN bus.
bool	SingleWire () const
	Indicate a single wire CAN bus.
void	R0 (bool flag)
	Optional R0 flag.
bool	R0 () const
	Optional R0 flag.
void	R1 (bool flag)
	Optional R1 flag.
bool	R1 () const
	Optional R1 flag.
void	FrameDuration (uint32_t duration)
	Frame duration in nano-seconds.
uint32_t	FrameDuration () const
	Frame duration in nano-seconds.
void	ToRaw (std::vector< uint8_t > &dest) const override
	Serialize the message.
void	FromRaw (const std::vector< uint8_t > &source) override
	Deserialize the message.
Public Member Functions inherited from bus::IBusMessage
	IBusMessage (BusMessageType type)
BusMessageType	Type () const
	Returns type of message.
void	Version (uint16_t version)
	Sets the vewrsion number for a message.
uint16_t	Version () const
	Returns the version number of the message.
uint32_t	Size () const
	Returns the total size of the message.
bool	Valid () const
	Returns true if the message is valid.
void	Timestamp (uint64_t timestamp)
	Sets the absolute time.
uint64_t	Timestamp () const
	Retuns the timestampe.
void	BusChannel (uint16_t channel)
	Sets the source channel.
uint16_t	BusChannel () const
	Returns the bus channel number.

Static Public Member Functions
static size_t	DlcToLength (uint8_t dlc)
	Return the data length by DLC.
Static Public Member Functions inherited from bus::IBusMessage
static std::shared_ptr< IBusMessage >	Create (BusMessageType type)
	Creates a message by its type.

Additional Inherited Members
Protected Member Functions inherited from bus::IBusMessage
void	Size (uint32_t size) const
	Sets the total size of the message.
void	Valid (bool valid) const
	Sets the message valid or invalid.

Detailed Description

The class implements an interface against a CAN Data Frame message. This message is the normal CAN messages while the other messages indicates some sort of exception or error.

The serialization is according to table below and uses little endian byte order.

CAN Data Frame Message Layout
Byte (Bits) Offset	Description	Size
0-17	Type of Message (enumerate)	18 bytes
18	Message ID (CAN Id + IDE)	uint32_t
22	DLC	uint8_t
23	Data Length	uint8_t
24	CRC	uint32_t
28:0	Direction (Rx=0, Tx=1)	1-bit
28:1	SRR	1-bit
28:2	EDL	1-bit
28:3	BRS	1-bit
28:4	ESI	1-bit
28:5	RTR	1-bit
28:6	R0	1-bit
28:7	R1	1-bit
29:0	Wake Up	1-bit
29:1	Single Wire	1-bit
30	Frame Duration (ns)/td>	uint32_t
34	Data Bytes	Data Length bytes

Member Function Documentation

◆ CanId()

uint32_t bus::CanDataFrame::CanId ( ) const

nodiscard

The CAN message ID identifies the message on a CAN bus. Note that there is a DBC message ID which is the CAN ID + highest bit 31 set if the CAN ID uses 29-bit addressing. This is a confusing naming that causes invalid handling of messages.

Returns: 29-bit CAN ID.

◆ DataBytes()

void bus::CanDataFrame::DataBytes ( const std::vector< uint8_t > & data )

This function sets the payload data bytes in the message. Note that this function also set the data length and DLC code.

Parameters

data

◆ DataLength()

void bus::CanDataFrame::DataLength ( uint8_t data_length )

The data length is not sent on the bus. Instead is it calculated from the DLC code. Note that the DataBytes() function fix both data length and the DLC code so this function is normally not used.

Parameters

data_length Number of payload data bytes.

◆ Dlc() [1/2]

uint8_t bus::CanDataFrame::Dlc ( ) const

inlinenodiscard

The DLC is equal to number of bytes for CAN messages but not for CAN FD messages.

Returns: Data length code for the message.

◆ Dlc() [2/2]

void bus::CanDataFrame::Dlc ( uint8_t dlc )

inline

Sets the data length code (DLC). The DLC is the same as data length for CAN but not for CAN FD. Note that the DataBytes() function fix both data length and the DLC code so this function is normally not used.

Parameters

dlc	Data length code.

◆ ExtendedId() [1/2]

bool bus::CanDataFrame::ExtendedId ( ) const

nodiscard

Returns: True if CAN ID uses extended addressing. Returns the extended CAN ID.

◆ ExtendedId() [2/2]

void bus::CanDataFrame::ExtendedId ( bool extended )

Parameters

extended True if CAN ID uses 29-bit addressing.

◆ FromRaw()

void bus::CanDataFrame::FromRaw ( const std::vector< uint8_t > & source )

overridevirtual

Reads in the byte array and desrialize the message.

Parameters

source Source buffer.

Reimplemented from bus::IBusMessage.

◆ MessageId() [1/2]

uint32_t bus::CanDataFrame::MessageId ( ) const

nodiscard

The message ID is the CAN ID with the highest bit 31 set if the CAN ID uses a 29-bit address.

Returns: DBC message ID.

◆ MessageId() [2/2]

void bus::CanDataFrame::MessageId ( uint32_t msg_id )

The message ID is the CAN ID + highest bit 31 set if the CAN ID uses extended 29-bit ID. The message ID is actually used in a DBC file and not sent on the CAN bus, well the extended bit is sent.

Parameters

msg_id DBC Message ID

◆ ToRaw()

void bus::CanDataFrame::ToRaw ( std::vector< uint8_t > & dest ) const

overridevirtual

Serialize the message to a destination byte array. The destination array size is set by the function.

Parameters

dest	Destination buffer.

Reimplemented from bus::IBusMessage.

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

include/bus/candataframe.h

	Bus Messages 1.0 Bus Message Serialization Library

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ CanId()

◆ DataBytes()

◆ DataLength()

◆ Dlc() [1/2]

◆ Dlc() [2/2]

◆ ExtendedId() [1/2]

◆ ExtendedId() [2/2]

◆ FromRaw()

◆ MessageId() [1/2]

◆ MessageId() [2/2]

◆ ToRaw()