Detailed Description

The QCanFrame class supports CAN data frames and CAN error frames. The method frameType() is used to distinguish between these formats. The frame type can be selected either by the constructor QCanFrame(const FrameType_e &) or by using setFrameType().

Data Frame

The QCanFrame class distinguishes the four message frame formats via the method frameFormat(), possible values are listed by the enumeration QCanFrame::FrameFormat_e.

Classic base frame format (CBFF)	QCanFrame::eFORMAT_CAN_STD
Classic extended frame format (CEFF)	QCanFrame::eFORMAT_CAN_EXT
FD base frame format (FBFF)	QCanFrame::eFORMAT_FD_STD
FD extended frame format (FEFF)	QCanFrame::eFORMAT_FD_EXT

The class provides two application specific fields with a size of 32-bit which are compliant are compliant to the CpCanMsg_s structure They can be accessed by the setMarker() and setUser() methods. An optional time-stamp is provided by the setTimeStamp() method.

Error Frame

A frame of type QCanFrame::eFRAME_TYPE_ERROR is used to inform about the actual error state (function errorState()) and the current values of the error counters (functions errorCounterReceive() and errorCounterTransmit()). In addition, it is possible to inform about the last error type which caused the error condition (function errorType()).

QCanFrame   clErrorFrameT;
 
//--------------------------------------------------------------------------
// set frame type to error frame
//
clErrorFrameT.setFrameType(QCanFrame::eFRAME_TYPE_ERROR);
 
clErrorFrameT.setErrorCounterReceive(32);
clErrorFrameT.setErrorCounterTransmit(64);

#include <qcan_frame.hpp>

Public Types
enum	ErrorType_e { eERROR_TYPE_NONE = 0 , eERROR_TYPE_BIT0 , eERROR_TYPE_BIT1 , eERROR_TYPE_STUFF , eERROR_TYPE_FORM , eERROR_TYPE_CRC , eERROR_TYPE_ACK }

enum	FrameFormat_e { eFORMAT_CAN_STD = 0 , eFORMAT_CAN_EXT , eFORMAT_FD_STD , eFORMAT_FD_EXT }

enum	FrameType_e { eFRAME_TYPE_UNKNOWN = 0 , eFRAME_TYPE_DATA , eFRAME_TYPE_ERROR }

Public Member Functions
	QCanFrame ()

	QCanFrame (const FrameType_e &ubTypeR)

	QCanFrame (const FrameFormat_e &ubFormatR, const uint32_t &ulIdentifierR=0, const uint8_t &ubDlcR=0)

	QCanFrame (const QCanFrame &clOtherR)

QCanFrame &	operator= (const QCanFrame &clOtherR)

bool	bitrateSwitch (void) const

uint8_t	data (const uint8_t &ubPosR) const

QByteArray	data (void) const

uint8_t	dataSize (void) const

uint16_t	dataUInt16 (const uint8_t &ubPosR, const bool &btMsbFirstR=false) const

uint32_t	dataUInt32 (const uint8_t &ubPosR, const bool &btMsbFirstR=false) const

uint8_t	dlc (void) const

uint8_t	errorCounterReceive (void) const

uint8_t	errorCounterTransmit (void) const

QCan::CAN_State_e	errorState (void) const

bool	errorStateIndicator (void) const

ErrorType_e	errorType (void) const

FrameFormat_e	frameFormat (void) const

FrameType_e	frameType (void) const

bool	fromByteArray (const QByteArray &clByteArrayR)

bool	fromCpCanMsg (const struct CpCanMsg_s *ptsCanMsgV)

uint32_t	identifier (void) const

bool	isExtended (void) const

bool	isRemote (void) const

uint32_t	marker (void) const

void	setBitrateSwitch (const bool &btBrsR=true)

void	setData (const uint8_t &ubPosR, const uint8_t &ubValueR)

void	setDataSize (uint8_t ubSizeV)

void	setDataUInt16 (const uint8_t &ubPosR, const uint16_t &uwValueR, const bool &btMsbFirstR=0)

void	setDataUInt32 (const uint8_t &ubPosR, const uint32_t &ulValueR, const bool &btMsbFirstR=0)

void	setDlc (uint8_t ubDlcV)

void	setErrorCounterReceive (const uint8_t &ubErrorCntR)

void	setErrorCounterTransmit (const uint8_t &ubErrorCntR)

void	setErrorState (QCan::CAN_State_e ubStateV)

void	setErrorType (ErrorType_e ubTypeV)

void	setErrorStateIndicator (const bool &btEsiR=true)

void	setFrameFormat (const FrameFormat_e &ubFormatR)

void	setFrameType (const FrameType_e &ubTypeR)

void	setIdentifier (uint32_t ulIdentifierV)

void	setMarker (const uint32_t &ulMarkerValueR)

void	setRemote (const bool &btRtrR=true)

void	setUser (const uint32_t &ulUserValueR)

void	setTimeStamp (const QCanTimeStamp &clTimeStampR)

QCanTimeStamp	timeStamp (void) const

QByteArray	toByteArray (void) const

bool	toCpCanMsg (struct CpCanMsg_s *ptsCanMsgV) const

virtual QString	toString (const bool &btShowTimeR=false, const bool &btShowDataSizeR=false) const

Member Enumeration Documentation

◆ ErrorType_e

enum QCanFrame::ErrorType_e

The enumeration ErrorType_e defines CAN error types.

Enumerator
eERROR_TYPE_NONE	no error
eERROR_TYPE_BIT0	Bit 0 error occurred
eERROR_TYPE_BIT1	Bit 1 error occurred
eERROR_TYPE_STUFF	Stuff error occurred
eERROR_TYPE_FORM	Form error occurred
eERROR_TYPE_CRC	CRC error occurred
eERROR_TYPE_ACK	Acknowledgement error occurred

◆ FrameFormat_e

enum QCanFrame::FrameFormat_e

This enumeration defines the CAN frame formats for classic CAN and CAN FD.

Enumerator
eFORMAT_CAN_STD	Classic CAN, Standard frame format
eFORMAT_CAN_EXT	Classic CAN, Extended frame format
eFORMAT_FD_STD	ISO CAN FD, Standard frame format
eFORMAT_FD_EXT	ISO CAN FD, Extended frame format

◆ FrameType_e

enum QCanFrame::FrameType_e

The enumeration FrameType_e defines the different CAN frame types.

Enumerator
eFRAME_TYPE_UNKNOWN	Unknown frame type
eFRAME_TYPE_DATA	Data frame
eFRAME_TYPE_ERROR	Error frame

Constructor & Destructor Documentation

◆ QCanFrame() [1/4]

QCanFrame::QCanFrame ( )

Constructs an empty classic standard CAN frame (frame format QCanFrame::eFORMAT_CAN_STD) with a DLC value of 0.

◆ QCanFrame() [2/4]

QCanFrame::QCanFrame ( const FrameType_e & ubTypeR )

Parameters

[in] ubTypeR Frame type

Constructs an empty data structure with a frame type of QCanFrame::FrameType_e.

◆ QCanFrame() [3/4]

QCanFrame::QCanFrame	(	const FrameFormat_e &	ubFormatR,
		const uint32_t &	ulIdentifierR = 0,
		const uint8_t &	ubDlcR = 0 )

Parameters

[in]	ubFormatR	CAN frame format
[in]	ulIdentifierR	CAN frame identifier
[in]	ubDlcR	CAN frame data length code

Constructs a CAN frame of type ubTypeR with an identifier value of ulIdentifierR and a DLC value of ubDlcR.

◆ QCanFrame() [4/4]

QCanFrame::QCanFrame ( const QCanFrame & clOtherR )

Parameters

[in] clOtherR reference to CAN frame

Constructs a copy of clOtherR.

Member Function Documentation

◆ bitrateSwitch()

bool QCanFrame::bitrateSwitch ( void ) const

Returns: true if bit-rate switch is set

See also: setBitrateSwitch()

The function returns true if the bit-rate switch bit is set for the CAN frame. For classic CAN frames the function always returns false.

◆ data() [1/2]

uint8_t QCanFrame::data ( const uint8_t & ubPosR ) const

Returns: Data at payload position ubPosR

Parameters

[in] ubPosR Index of payload

The function returns the data stored at payload position ubPosR. The first position starts at index 0. If the index position is out of range, the function will return 0. The maximum index position for a CAN frame is dataSize() - 1, as depicted in the following code example.

QCanFrame  clCanFrameT;
..
for (uint8_t ubPosT = 0; ubPosT < clCanFrameT.dataSize(); ubPosT++)
{
   //------------------------------------------------
   // print payload of CAN frame
   //
   cout << hex << clCanFrameT.data(ubPosT);
}

◆ data() [2/2]

QByteArray QCanFrame::data ( void ) const

Returns: Data of CAN frame

The function returns the data stored in the CAN frame as QByteArray.

◆ dataSize()

uint8_t QCanFrame::dataSize ( void ) const

Returns: Size of payload in bytes

See also: dlc()

The function returns the number of bytes that are valid for the CAN frame. The possible value range is 0 to 8 for classic CAN frames and 0 to 64 for CAN FD frames. In order to obtain the data length code (DLC) use the dlc() function.

◆ dataUInt16()

uint16_t QCanFrame::dataUInt16	(	const uint8_t &	ubPosR,
		const bool &	btMsbFirstR = false ) const

Returns: Unsigned 16-bit data

Parameters

[in]	ubPosR	Index of payload
[in]	btMsbFirstR	Byte order

See also: setDataUInt16()

The function returns an unsigned 16-bit value (uint16_t) starting at position ubPosR of the CAN payload.

◆ dataUInt32()

uint32_t QCanFrame::dataUInt32	(	const uint8_t &	ubPosR,
		const bool &	btMsbFirstR = false ) const

Returns: Unsigned 32-bit data

Parameters

[in]	ubPosR	Index of payload
[in]	btMsbFirstR	Byte order

See also: setDataUInt32()

The function returns an unsigned 32-bit value (uint32_t) starting at position ubPosR of the CAN payload.

◆ dlc()

uint8_t QCanFrame::dlc ( void ) const

Returns: Data length code (DLC)

See also: dataSize()

The function returns the DLC value (data length code) for the CAN frame. The possible value range is 0 to 8 for classic CAN frames and 0 to 15 for CAN FD frames. In order to obtain the number of bytes inside the payload use dataSize().

◆ errorCounterReceive()

uint8_t QCanFrame::errorCounterReceive ( void ) const

Returns: Value of receive error counter

See also: setErrorCounterReceive()

The functions returns the current value of the receive error counter for an error frame (frame type QCanFrame::eFRAME_TYPE_ERROR). For a data frame the function returns 0.

◆ errorCounterTransmit()

uint8_t QCanFrame::errorCounterTransmit ( void ) const

Returns: Value of transmit error counter

See also: setErrorCounterTransmit()

This functions returns the current value of the transmit error counter for an error frame (frame type QCanFrame::eFRAME_TYPE_ERROR). For a data frame the function returns 0. A value of 255 leads to a bus-off condition (QCan::eCAN_STATE_BUS_OFF).

◆ errorState()

QCan::CAN_State_e QCanFrame::errorState ( void ) const

Returns: Current error state

See also: setErrorState()

This functions returns the current error state, defined by the enumeration QCan::CAN_State_e.

◆ errorStateIndicator()

bool QCanFrame::errorStateIndicator ( void ) const

Returns: true if error state indicator is set

See also: setErrorStateIndicator()

The function returns true if the error state indicator bit is set inside a CAN FD frame. For classic CAN frames the function always returns false.

◆ errorType()

ErrorType_e QCanFrame::errorType ( void ) const

Returns: Error type

See also: setErrorType()

This functions returns the error type which caused the last error condition.

◆ frameFormat()

FrameFormat_e QCanFrame::frameFormat ( void ) const

Returns: Frame format

See also: setFrameFormat()

The function returns the CAN frame format, defined by the FrameFormat_e enumeration.

◆ frameType()

FrameType_e QCanFrame::frameType ( void ) const

Returns: Frame type

See also: setFrameType()

The function returns the frame type defined by FrameType_e.

◆ fromByteArray()

bool QCanFrame::fromByteArray ( const QByteArray & clByteArrayR )

Parameters

[in] clByteArrayR Byte array containing CAN frame data

Returns: Conversion result

See also: toByteArray()

The function converts a QByteArray object to a QCanFrame object. On success, the function returns true, otherwise false.

◆ fromCpCanMsg()

bool QCanFrame::fromCpCanMsg ( const struct CpCanMsg_s * ptsCanMsgV )

Parameters

[in] ptsCanMsgV Pointer to CANpie message structure

Returns: Conversion result

See also: toCpCanMsg()

The function converts a structure of type CpCanMsg_ts to a QCanFrame object. On success, the function returns true, otherwise false.

◆ identifier()

uint32_t QCanFrame::identifier ( void ) const

Returns: Identifier of CAN frame

See also: setIdentifier()

The function returns the identifier value. In order to distinguish between standard (11 bit) and extended (29 bit) frame formats use either frameFormat() or isExtended().

◆ isExtended()

bool QCanFrame::isExtended ( void ) const

Returns: true if Extended CAN frame

See also: frameType()

The function returns true if the frame type is either eFORMAT_CAN_EXT or eFORMAT_FD_EXT, otherwise it will return false;

◆ isRemote()

bool QCanFrame::isRemote ( void ) const

Returns: true if Remote frame

See also: setRemote()

The function returns true if the CAN frame is a Remote frame. Please note that only classic CAN frames have this attribute, i.e. a ISO CAN FD frame will always return false.

◆ marker()

uint32_t QCanFrame::marker ( void ) const

Returns: Marker of CAN frame

See also: setMarker()

The function returns the message marker of the frame.

◆ operator=()

QCanFrame & QCanFrame::operator= ( const QCanFrame & clOtherR )

Parameters

[in] clOtherR reference to CAN frame

Returns: Reference to this CAN frame

Assigns clOtherR to this CAN frame and returns a reference to this CAN frame.

◆ setBitrateSwitch()

void QCanFrame::setBitrateSwitch ( const bool & btBrsR = true )

Parameters

[in] btBrsR Value of BRS bit

See also: bitrateSwitch()

The function sets the value of the bit-rate switch (BRS) bit of a ISO CAN FD frame. The function has no impact on a classic CAN frame.

◆ setData()

void QCanFrame::setData	(	const uint8_t &	ubPosR,
		const uint8_t &	ubValueR )

Parameters

[in]	ubPosR	Index of payload
[in]	ubValueR	Data of payload

See also: data()

This function sets the data in a CAN message. The parameter ubPosR must be within the range 0 .. 7 for classic frames and 0 .. 63 for FD frames.

◆ setDataSize()

void QCanFrame::setDataSize ( uint8_t ubSizeV )

Parameters

[in] ubSizeV Size of payload

See also: setDlc()

The function sets the number of data bytes that are valid for the CAN frame. The possible value range is 0 to 8 for classic CAN frames and 0 to 64 for CAN FD frames.

◆ setDataUInt16()

void QCanFrame::setDataUInt16	(	const uint8_t &	ubPosR,
		const uint16_t &	uwValueR,
		const bool &	btMsbFirstR = 0 )

Parameters

[in]	ubPosR	Index of payload
[in]	uwValueR	16-bit value
[in]	btMsbFirstR	Byte order

See also: dataUInt16()

The function sets an unsigned 16-bit value (uint16_t) uwValueR starting at position ubPosR of the CAN payload.

◆ setDataUInt32()

void QCanFrame::setDataUInt32	(	const uint8_t &	ubPosR,
		const uint32_t &	ulValueR,
		const bool &	btMsbFirstR = 0 )

Parameters

[in]	ubPosR	Index of payload
[in]	ulValueR	32-bit value
[in]	btMsbFirstR	Byte order

See also: dataUInt32()

The function sets an unsigned 32-bit value (uint32_t) ulValueR starting at position ubPosR of the CAN payload.

◆ setDlc()

void QCanFrame::setDlc ( uint8_t ubDlcV )

Parameters

[in] ubDlcV DLC value

See also: setDataSize()

The function sets the DLC value (data length code) for a CAN data frame. The possible value range is 0 to 8 for classic CAN frames and 0 to 15 for CAN FD frames. If the value is out of range it is not stored in the frame object.

◆ setErrorCounterReceive()

void QCanFrame::setErrorCounterReceive ( const uint8_t & ubErrorCntR )

Parameters

[in] ubErrorCntR Receive error counter value

See also: errorCounterReceive()

The functions sets the receive error counter for an error frame (frame type QCanFrame::eFRAME_TYPE_ERROR). For a data frame the function has no impact. Passing a value greater than 127 will set the error state to error passive (QCan::eCAN_STATE_BUS_PASSIVE).

◆ setErrorCounterTransmit()

void QCanFrame::setErrorCounterTransmit ( const uint8_t & ubErrorCntR )

Parameters

[in] ubErrorCntR Transmit error counter value

See also: errorCounterTransmit()

The functions sets the transmit error counter for an error frame (frame type QCanFrame::eFRAME_TYPE_ERROR). For a data frame the function has no impact. Passing a value greater than 127 will set the error state to error passive (QCan::eCAN_STATE_BUS_PASSIVE). A value of 255 will set the error state to bus-off (QCan::eCAN_STATE_BUS_OFF).

◆ setErrorState()

void QCanFrame::setErrorState ( QCan::CAN_State_e ubStateV )

Parameters

[in] ubStateV Error state value

See also: errorState()

This functions sets the current error state, defined by the enumeration QCan::CAN_State_e.

◆ setErrorStateIndicator()

void QCanFrame::setErrorStateIndicator ( const bool & btEsiR = true )

Parameters

[in] btEsiR Value of ESI bit

See also: errorStateIndicator()

The function sets the value of the Error State Indicator (ESI) bit of a ISO CAN FD frame. The function has no impact on a classic CAN frame.

◆ setErrorType()

void QCanFrame::setErrorType ( ErrorType_e ubTypeV )

Parameters

[in] ubTypeV Error type value

See also: errorType()

This functions sets the error type which caused the last error condition.

◆ setFrameFormat()

void QCanFrame::setFrameFormat ( const FrameFormat_e & ubFormatR )

Parameters

[in] ubFormatR CAN frame format

See also: frameType()

The function sets the CAN frame format, defined by the FrameFormat_e enumeration. Please note that a change of frame format has an impact on several internal CAN frame bits:

Changing from Classic CAN to ISO CAN FD
In this case the RTR bit is cleared and the FDF bit is set. Both ESI and BRS are cleared by default.

Changing from ISO CAN FD to Classic CAN
In this case the the FDF bit is cleared, also the ESI and BRS bits are cleared. The RTR bit is cleared by default. If the current DLC value exceeds the value 8, the DLC value will be set to 8.

◆ setFrameType()

void QCanFrame::setFrameType ( const FrameType_e & ubTypeR )

Parameters

[in] ubTypeR CAN frame type

See also: frameType()

The function sets the CAN frame format, defined by the FrameType_e enumeration. Please note that changing the frame type will set all data bytes to 0.

◆ setIdentifier()

void QCanFrame::setIdentifier ( uint32_t ulIdentifierV )

Parameters

[in] ulIdentifierV CAN frame type

See also: identifier()

The function sets the identifier value of a CAN frame. Depending on the CAN frame type (Standard or Extended) the value is truncated to a 11-bit value (for Standard frames) or a 29-bit value (for Extended frames).

◆ setMarker()

void QCanFrame::setMarker ( const uint32_t & ulMarkerValueR )

Parameters

[in] ulMarkerValueR Marker value

See also: marker()

The function sets a message marker inside the CAN frame. The purpose of the message marker is application specific.

◆ setRemote()

void QCanFrame::setRemote ( const bool & btRtrR = true )

Parameters

[in] btRtrR Value of RTR bit

See also: isRemote()

The function sets the value of the Remote Transmission Request (RTR) bit of a classic CAN frame.

◆ setTimeStamp()

void QCanFrame::setTimeStamp ( const QCanTimeStamp & clTimeStampR )

inline

Parameters

[in] clTimeStampR Time-stamp

See also: timeStamp()

The function sets the time-stamp of the CAN frame.

◆ setUser()

void QCanFrame::setUser ( const uint32_t & ulUserValueR )

Parameters

[in] ulUserValueR User value

See also: user()

The function sets a user-defined value inside the CAN frame. The purpose of the field is application specific.

◆ timeStamp()

QCanTimeStamp QCanFrame::timeStamp ( void ) const

inline

Returns: Time-stamp

See also: setTimeStamp()

The function returns the time-stamp value of the CAN frame.

◆ toByteArray()

QByteArray QCanFrame::toByteArray ( void ) const

Returns: QByteArray

See also: fromByteArray()

The function converts a QCanFrame object to a QByteArray. The size of the array is defined by QCAN_FRAME_ARRAY_SIZE.

◆ toCpCanMsg()

bool QCanFrame::toCpCanMsg ( struct CpCanMsg_s * ptsCanMsgV ) const

Parameters

[in] ptsCanMsgV Pointer to CANpie message structure

Returns: Conversion result

See also: fromCpCanMsg()

The function converts a QCanFrame to a structure of type CpCanMsg_ts. On success, the function returns true, otherwise false.

◆ toString()

virtual QString QCanFrame::toString	(	const bool &	btShowTimeR = false,
		const bool &	btShowDataSizeR = false ) const

virtual

Returns: CAN frame as QString object

Parameters

[in]	btShowTimeR	Print time-stamp
[in]	btShowDataSizeR	Print data size instead of DLC value

The function converts a QCanFrame object to a QString. The output depends on the frame type and frame format. Frame formats are denoted with the abbreviations CBFF, CEFF, FBFF and FEFF. For CAN FD frames the fields bit-rate switch (BRS) and error state indicator (ESI) are shown if set. The parameter btShowDataSizeR defines if the DLC value (dlc()) is shown or the data size (dataSize()).

     100  CBFF          2  11 22
18EEFF00  CEFF          3  45 AB 12
     200  FBFF BRS,ESI  9  11 22 00 00 00 00 00 00 00 00 00 00
  2AFF33  FEFF BRS     10  88 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
   Error frame ----------  Error passive, Error counter: Rcv=128, Trm=32

Detailed Description

Data Frame

Error Frame

Public Types

Public Member Functions

Member Enumeration Documentation

◆ ErrorType_e

◆ FrameFormat_e

◆ FrameType_e

Constructor & Destructor Documentation

◆ QCanFrame() [1/4]

◆ QCanFrame() [2/4]

◆ QCanFrame() [3/4]

◆ QCanFrame() [4/4]

Member Function Documentation

◆ bitrateSwitch()

◆ data() [1/2]

◆ data() [2/2]

◆ dataSize()

◆ dataUInt16()

◆ dataUInt32()

◆ dlc()

◆ errorCounterReceive()

◆ errorCounterTransmit()

◆ errorState()

◆ errorStateIndicator()

◆ errorType()

◆ frameFormat()

◆ frameType()

◆ fromByteArray()

◆ fromCpCanMsg()

◆ identifier()

◆ isExtended()

◆ isRemote()

◆ marker()

◆ operator=()

◆ setBitrateSwitch()

◆ setData()

◆ setDataSize()

◆ setDataUInt16()

◆ setDataUInt32()

◆ setDlc()

◆ setErrorCounterReceive()

◆ setErrorCounterTransmit()

◆ setErrorState()

◆ setErrorStateIndicator()

◆ setErrorType()

◆ setFrameFormat()

◆ setFrameType()

◆ setIdentifier()

◆ setMarker()

◆ setRemote()

◆ setTimeStamp()

◆ setUser()

◆ timeStamp()

◆ toByteArray()

◆ toCpCanMsg()

◆ toString()