CAN Data Link Layer More...

Detailed Description

CAN Data Link Layer

The Data Link Layer is composed of the device, router, pkt and dll files. It can be used to send and receive raw CAN frames through multiple CAN controllers.

Files
file	can.h
	Definitions high-level CAN interface.

file	device.h
	Definitions of CAN device interface.

file	dll.h
	Definitions of low-level CAN DLL interface.

file	pkt.h
	CAN memory allocation module.

file	raw.h
	Definitions high-level RAW CAN interface.

file	router.h
	Functions for routing RX can frames.

Data Structures
struct	can_frame
	Controller Area Network frame. More...

struct	can_filter
	Controller Area Network filter. More...

struct	can_bittiming
	CAN bit-timing parameters. More...

struct	can_bittiming_const
	CAN hardware-dependent bit-timing constant. More...

Typedefs
typedef uint32_t	canid_t
	Controller Area Network Identifier structure.

typedef struct can_frame	can_frame_t
	CAN frame.

Enumerations
enum	can_state { CAN_STATE_ERROR_ACTIVE = 0 , CAN_STATE_ERROR_WARNING , CAN_STATE_ERROR_PASSIVE , CAN_STATE_BUS_OFF , CAN_STATE_STOPPED , CAN_STATE_SLEEPING , CAN_STATE_MAX }
	CAN operational and error states. More...

#define	CAN_MAX_DLEN (8)
	Max data length for classic and FD CAN frames (compliant with libsocketcan macros)

#define	CANFD_MAX_DLEN (64)
	CAN FD maximum data length.

CAN_ID flags and masks
#define	CAN_EFF_FLAG (0x80000000U)
	EFF/SFF is set in the MSB.

#define	CAN_RTR_FLAG (0x40000000U)
	remote transmission request

#define	CAN_ERR_FLAG (0x20000000U)
	error message frame

#define	CAN_SFF_MASK (0x000007FFU)
	standard frame format (SFF)

#define	CAN_EFF_MASK (0x1FFFFFFFU)
	extended frame format (EFF)

#define	CAN_ERR_MASK (0x1FFFFFFFU)
	omit EFF, RTR, ERR flags

CAN FD flags extracted from libsocketcan
#define	CANFD_BRS 0x01
	bit rate switch (second bitrate for payload data)

#define	CANFD_ESI 0x02
	error state indicator of the transmitting node

#define	CANFD_FDF 0x04
	mark CAN FD for dual use of struct canfd_frame

Macro Definition Documentation

◆ CAN_EFF_FLAG

#define CAN_EFF_FLAG (0x80000000U)

EFF/SFF is set in the MSB.

Definition at line 56 of file can.h.

◆ CAN_EFF_MASK

#define CAN_EFF_MASK (0x1FFFFFFFU)

extended frame format (EFF)

Definition at line 62 of file can.h.

◆ CAN_ERR_FLAG

#define CAN_ERR_FLAG (0x20000000U)

error message frame

Definition at line 58 of file can.h.

◆ CAN_ERR_MASK

#define CAN_ERR_MASK (0x1FFFFFFFU)

omit EFF, RTR, ERR flags

Definition at line 63 of file can.h.

◆ CAN_MAX_DLEN

#define CAN_MAX_DLEN (8)

Max data length for classic and FD CAN frames (compliant with libsocketcan macros)

Classic CAN maximum data length

Definition at line 47 of file can.h.

◆ CAN_RTR_FLAG

#define CAN_RTR_FLAG (0x40000000U)

remote transmission request

Definition at line 57 of file can.h.

◆ CAN_SFF_MASK

#define CAN_SFF_MASK (0x000007FFU)

standard frame format (SFF)

Definition at line 61 of file can.h.

◆ CANFD_BRS

#define CANFD_BRS 0x01

bit rate switch (second bitrate for payload data)

Definition at line 70 of file can.h.

◆ CANFD_ESI

#define CANFD_ESI 0x02

error state indicator of the transmitting node

Definition at line 71 of file can.h.

◆ CANFD_FDF

#define CANFD_FDF 0x04

mark CAN FD for dual use of struct canfd_frame

Definition at line 72 of file can.h.

◆ CANFD_MAX_DLEN

#define CANFD_MAX_DLEN (64)

CAN FD maximum data length.

Definition at line 48 of file can.h.

Typedef Documentation

◆ can_frame_t

typedef struct can_frame can_frame_t

CAN frame.

Definition at line 179 of file can.h.

◆ canid_t

typedef uint32_t canid_t

Controller Area Network Identifier structure.

bit 0-28 : CAN identifier (11/29 bit) right aligned for 11 bit bit 29 : error message frame flag (0 = data frame, 1 = error message) bit 30 : remote transmission request flag (1 = rtr frame) bit 31 : frame format flag (0 = standard 11 bit, 1 = extended 29 bit)

Definition at line 96 of file can.h.

Enumeration Type Documentation

◆ can_state

enum can_state

CAN operational and error states.

Enumerator
CAN_STATE_ERROR_ACTIVE	RX/TX error count < 96.
CAN_STATE_ERROR_WARNING	RX/TX error count < 128.
CAN_STATE_ERROR_PASSIVE	RX/TX error count < 256.
CAN_STATE_BUS_OFF	RX/TX error count >= 256.
CAN_STATE_STOPPED	Device is stopped.
CAN_STATE_SLEEPING	Device is sleeping.

Definition at line 78 of file can.h.