CAN library. More...

Collaboration diagram for CAN:

Classes
struct	CanStorage
	Storage class for the device ID and RX data. More...

struct	CanSettings
	CAN Settings. More...

union	CanId
	CAN message ID. More...

struct	CanMessage
	CAN message structure. More...

struct	CanQueue
	CAN queue data structure to store received CAN messages. More...

struct	CanWatchDog
	Software defined CAN watchdog. More...

Macros
#define	CAN_TIMEOUT_MS 5U
	Maximum time permitted for a CAN transaction.

#define	CAN_HW_DEV_INTERFACE "vcan0"

#define	CAN_MSG_MAX_STD_IDS (1 << 11)
	Maximum permitted CAN ID for 11-bit identifiers.

#define	CAN_QUEUE_SIZE 64U
	Maximum number of CAN messages permitted for the CAN queue.

#define	can_queue_init(can_queue)

#define	can_queue_push(can_queue, source) queue_send(&(can_queue)->queue, (source), 0)

#define	can_queue_push_from_isr(can_queue, source, high_prio_woken) queue_send_from_isr(&(can_queue)->queue, (source), high_prio_woken)

#define	can_queue_peek(can_queue, dest) queue_peek(&(can_queue)->queue, (dest), 0)

#define	can_queue_pop(can_queue, dest) queue_receive(&(can_queue)->queue, (dest), 0)

#define	can_queue_pop_from_isr(can_queue, dest, higher_prio_woken) queue_receive_from_isr(&(can_queue)->queue, (dest), high_prio_woken)

#define	can_queue_size(can_queue) queue_get_num_items(&(can_queue)->queue)

Typedefs
typedef struct CanStorage	CanStorage
	Storage class for the device ID and RX data.

typedef struct CanSettings	CanSettings
	CAN Settings. More...

typedef uint32_t	CanMessageId
	CAN message ID. More...

typedef union CanId	CanId
	CAN message ID.

typedef struct CanMessage	CanMessage
	CAN message structure. More...

typedef struct CanQueue	CanQueue
	CAN queue data structure to store received CAN messages. More...

typedef struct CanWatchDog	CanWatchDog
	Software defined CAN watchdog.

Enumerations
enum	CanHwBusStatus { CAN_HW_BUS_STATUS_OK = 0 , CAN_HW_BUS_STATUS_ERROR , CAN_HW_BUS_STATUS_OFF }
	CAN Bus status flags. More...

enum	CanHwBitrate { CAN_HW_BITRATE_125KBPS , CAN_HW_BITRATE_250KBPS , CAN_HW_BITRATE_500KBPS , CAN_HW_BITRATE_1000KBPS , NUM_CAN_HW_BITRATES }
	Selection for the supported CAN Bitrates. More...

Functions
StatusCode	can_init (CanStorage storage, const CanSettings settings)
	Initialize the CAN interface. More...

StatusCode	can_add_filter_in (CanMessageId msg_id)
	Sets a filter on the CAN interface. More...

StatusCode	can_transmit (const CanMessage *msg)
	Transmits CAN data on the bus. More...

StatusCode	can_receive (const CanMessage *msg)
	Receives CAN data from the bus. More...

StatusCode	run_can_tx_all ()
	Transmit all CAN data. More...

StatusCode	run_can_tx_fast ()
	Transmit all fast-cycle CAN data. More...

StatusCode	run_can_tx_medium ()
	Transmit all medium-cycle CAN data. More...

StatusCode	run_can_tx_slow ()
	Transmit all slow-cycle CAN data. More...

StatusCode	run_can_rx_all ()
	Receive all CAN data. More...

StatusCode	clear_rx_struct ()
	Clear the RX data struct. More...

StatusCode	clear_tx_struct ()
	Clear the TX data struct. More...

StatusCode	can_hw_init (const CanQueue rx_queue, const CanSettings settings)
	Initialize the CAN interface. More...

StatusCode	can_hw_add_filter_in (uint32_t mask, uint32_t filter, bool extended)
	Sets a filter on the CAN interface. More...

CanHwBusStatus	can_hw_bus_status (void)
	Fetches the CAN bus status. More...

StatusCode	can_hw_transmit (uint32_t id, bool extended, const uint8_t *data, size_t len)
	Transmits CAN data on the bus. More...

bool	can_hw_receive (uint32_t id, bool extended, uint64_t data, size_t len)
	Receives CAN data from the bus. More...

StatusCode	check_all_can_watchdogs ()
	Checks all CAN watchdogs. More...

StatusCode	check_fast_can_watchdogs ()
	Checks CAN watchdogs for messages in fast-cycle. More...

StatusCode	check_medium_can_watchdogs ()
	Checks CAN watchdogs for messages in medium-cycle. More...

StatusCode	check_slow_can_watchdogs ()
	Checks CAN watchdogs for messages in slow-cycle. More...

void	clear_all_rx_received ()

void	clear_fast_rx_received ()

void	clear_medium_rx_received ()

void	clear_slow_rx_received ()

Detailed Description

CAN library.

Macro Definition Documentation

◆ can_queue_init

#define can_queue_init ( can_queue )

Value:

  ({                                                                \
    Queue* queue       = &(can_queue)->queue;                       \
    queue->num_items   = CAN_QUEUE_SIZE;                            \
    queue->item_size   = sizeof(CanMessage);                        \
    queue->storage_buf = (uint8_t*) (&(can_queue)->msg_nodes);      \
    queue_init(&(can_queue)->queue);                                \
  })

Typedef Documentation

◆ CanMessage

typedef struct CanMessage CanMessage

CAN message structure.

CAN ID is subjected to arbitration where lower ID's are given higher priority Extended ID flag indicates a 29-bit ID or an 11-bit ID Data length code ias 4 bit value indicating the number of bytes in the payload CAN Frames hold 8 bytes of data at most

◆ CanMessageId

typedef uint32_t CanMessageId

CAN message ID.

11 Bits in standard mode 29 Bits in extended mode

◆ CanQueue

typedef struct CanQueue CanQueue

CAN queue data structure to store received CAN messages.

CAN data received is stored in the CanQueue data structure The Queue can hold a maximum of 64 CAN messages

◆ CanSettings

typedef struct CanSettings CanSettings

CAN Settings.

TX Pin will transmit data. RX pin will receive data. The bitrate is the number of bits sent per second. The device ID is the CAN ID of the STM32 node. Loopback will internally connect the transmit and receive CAN lines for testing. Silent mode is used for only listening to the bus.

Enumeration Type Documentation

◆ CanHwBitrate

enum CanHwBitrate

Selection for the supported CAN Bitrates.

CAN bit timing is composed of multiple time segments:

Synchronization Segment (Sync_Seg): Allows resynchronization
Propagation Segment (Prop_Seg): Compensates for physical delays
Phase Buffer Segments (Phase_Seg1 and Phase_Seg2):
- Absorb time quanta variations
- Provide sampling point adjustment
  Note
  Typical sampling occurs between 75-80% of bit time Higher bitrates require shorter time quantas Bitrate selection impacts signal reliability and bus length

Enumerator
CAN_HW_BITRATE_125KBPS	125 KBits per second
CAN_HW_BITRATE_250KBPS	250 KBits per second
CAN_HW_BITRATE_500KBPS	500 KBits per second
CAN_HW_BITRATE_1000KBPS	1000 KBits per second
NUM_CAN_HW_BITRATES	Number of supported bit rates

◆ CanHwBusStatus

enum CanHwBusStatus

CAN Bus status flags.

Enumerator
CAN_HW_BUS_STATUS_OK	CAN Bus is operating correctly
CAN_HW_BUS_STATUS_ERROR	CAN Bus has detected an error
CAN_HW_BUS_STATUS_OFF	CAN Bus is not initialized

Function Documentation

◆ can_add_filter_in()

StatusCode can_add_filter_in ( CanMessageId msg_id )

Sets a filter on the CAN interface.

Parameters

msg_id Message ID of the message to filter

Returns: STATUS_CODE_OK if the filter is added successfully STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ can_hw_add_filter_in()

StatusCode can_hw_add_filter_in	(	uint32_t	mask,
		uint32_t	filter,
		bool	extended
	)

Sets a filter on the CAN interface.

The filter works as such: if INCOMING_MSG_ID & mask == filter & mask, the message is handled

Parameters

mask	Determines which bits in the received ID are considered during filtering
filter	Specifies the pattern the CAN ID must adhere to
extended	Boolean to use CAN extended ID feature

Returns: STATUS_CODE_OK if adding the filter succeeded STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect

◆ can_hw_bus_status()

CanHwBusStatus can_hw_bus_status ( void )

Fetches the CAN bus status.

Returns: CAN_HW_BUS_STATUS_OK if bus is running CAN_HW_BUS_STATUS_ERROR if error is detected in the CAN bus CAN_HW_BUS_STATUS_OFF if bus is not initialized

◆ can_hw_init()

StatusCode can_hw_init	(	const CanQueue *	rx_queue,
		const CanSettings *	settings
	)

Initialize the CAN interface.

Parameters

rx_queue	Pointer to the CAN RX queue
settings	Pointer to the CAN settings

Returns: STATUS_CODE_OK if initialization succeeded STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ can_hw_receive()

bool can_hw_receive	(	uint32_t *	id,
		bool *	extended,
		uint64_t *	data,
		size_t *	len
	)

Receives CAN data from the bus.

Parameters

id	Pointer to store the CAN ID received
extended	Pointer to a flag to indicate CAN extended ID feature
data	Pointer to a buffer to store data
len	Pointer to the number of CAN messages received

Returns: true if data is retrieved successfully false if one of the parameters are incorrect or internal error occurred

◆ can_hw_transmit()

StatusCode can_hw_transmit	(	uint32_t	id,
		bool	extended,
		const uint8_t *	data,
		size_t	len
	)

Transmits CAN data on the bus.

Parameters

id	CAN message ID
extended	Boolean to use CAN extended ID feature
data	Pointer to the data to transmit
len	Size of the data to transfer

Returns: STATUS_CODE_OK if data is transmitted successfully STATUS_CODE_RESOURCE_EXHAUSTED if CAN mailbox is full STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect

◆ can_init()

StatusCode can_init	(	CanStorage *	storage,
		const CanSettings *	settings
	)

Initialize the CAN interface.

Parameters

storage	Pointer to the CAN storage
settings	Pointer to the CAN settings

Returns: STATUS_CODE_OK if initialization succeeded STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect STATUS_CODE_INTERNAL_ERROR if initialization fails

◆ can_receive()

StatusCode can_receive ( const CanMessage * msg )

Receives CAN data from the bus.

Parameters

msg	Pointer to the message to update on receive

Returns: STATUS_CODE_OK if data is retrieved successfully STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect STATUS_CODE_UNINITIALIZED if the CAN bus is not initialized

◆ can_transmit()

StatusCode can_transmit ( const CanMessage * msg )

Transmits CAN data on the bus.

Parameters

msg	Pointer to the message to transmit

Returns: STATUS_CODE_OK if data is transmitted successfully STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect STATUS_CODE_UNINITIALIZED if the CAN bus is not initialized

◆ check_all_can_watchdogs()

StatusCode check_all_can_watchdogs ( )

Checks all CAN watchdogs.

This will throw a LOG_WARN if a message has missed its watchdog

Returns: STATUS_CODE_OK if all watchdogs are checked succesfully

◆ check_fast_can_watchdogs()

StatusCode check_fast_can_watchdogs ( )

Checks CAN watchdogs for messages in fast-cycle.

This will throw a LOG_WARN if a message has missed its watchdog

Returns: STATUS_CODE_OK if all watchdogs are checked succesfully

◆ check_medium_can_watchdogs()

StatusCode check_medium_can_watchdogs ( )

Checks CAN watchdogs for messages in medium-cycle.

This will throw a LOG_WARN if a message has missed its watchdog

Returns: STATUS_CODE_OK if all watchdogs are checked succesfully

◆ check_slow_can_watchdogs()

StatusCode check_slow_can_watchdogs ( )

Checks CAN watchdogs for messages in slow-cycle.

This will throw a LOG_WARN if a message has missed its watchdog

Returns: STATUS_CODE_OK if all watchdogs are checked succesfully

◆ clear_rx_struct()

StatusCode clear_rx_struct ( )

Clear the RX data struct.

Returns: STATUS_CODE_OK if initialization succeeded STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ clear_tx_struct()

StatusCode clear_tx_struct ( )

Clear the TX data struct.

Returns: STATUS_CODE_OK if initialization succeeded STATUS_CODE_INVALID_ARGS if one of the parameters are incorrect STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ run_can_rx_all()

StatusCode run_can_rx_all ( )

Receive all CAN data.

Returns: STATUS_CODE_OK if the cache is cleared successfully STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ run_can_tx_all()

StatusCode run_can_tx_all ( )

Transmit all CAN data.

Returns: STATUS_CODE_OK if the cache is cleared successfully STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ run_can_tx_fast()

StatusCode run_can_tx_fast ( )

Transmit all fast-cycle CAN data.

Returns: STATUS_CODE_OK if the cache is cleared successfully STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ run_can_tx_medium()

StatusCode run_can_tx_medium ( )

Transmit all medium-cycle CAN data.

Returns: STATUS_CODE_OK if the cache is cleared successfully STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

◆ run_can_tx_slow()

StatusCode run_can_tx_slow ( )

Transmit all slow-cycle CAN data.

Returns: STATUS_CODE_OK if the cache is cleared successfully STATUS_CODE_INTERNAL_ERROR if HAL initialization fails

Classes

Macros

Typedefs

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ can_queue_init

Typedef Documentation

◆ CanMessage

◆ CanMessageId

◆ CanQueue

◆ CanSettings

Enumeration Type Documentation

◆ CanHwBitrate

◆ CanHwBusStatus

Function Documentation

◆ can_add_filter_in()

◆ can_hw_add_filter_in()

◆ can_hw_bus_status()

◆ can_hw_init()

◆ can_hw_receive()

◆ can_hw_transmit()

◆ can_init()

◆ can_receive()

◆ can_transmit()

◆ check_all_can_watchdogs()

◆ check_fast_can_watchdogs()

◆ check_medium_can_watchdogs()

◆ check_slow_can_watchdogs()

◆ clear_rx_struct()

◆ clear_tx_struct()

◆ run_can_rx_all()

◆ run_can_tx_all()

◆ run_can_tx_fast()

◆ run_can_tx_medium()

◆ run_can_tx_slow()