CANDeviceManager Class Reference

#include <can_man.h>

Public Member Functions
virtual void	init (unsigned int base_address, unsigned int bit_speed, BYTE extended_frame)
virtual int	interrupt (CircularBuffer *in_buff, CircularBuffer *out_buff, can_filter_t filter)
virtual void	send (CircularBuffer *out_buff)
virtual can_msg_t	read (CircularBuffer *in_buff)
virtual int	write (CircularBuffer *out_buff, can_msg_t *pmsg)
virtual can_err_count_t	clear_errs ()
virtual can_err_count_t	get_errs ()
virtual void	tx_process_interrupt (CircularBuffer *out_buff)
virtual void	rx_process_interrupt (CircularBuffer *in_buff, can_filter_t filter)
virtual	~CANDeviceManager ()

Public Attributes
int	can_timeout_count = 0
int	tx_buffer_flush = 0
int	can_notify_client_err = 0
int	mask_count_non_zero = 0

Detailed Description

CAN Device Manager class.

This object is responsible for initializing and interacting with the CAN card. CAN messages are received through the SJA1000 chip, a blank.

Constructor & Destructor Documentation

~CANDeviceManager()

CANDeviceManager::~CANDeviceManager ( )

virtual

Virtual destructor.

Member Function Documentation

clear_errs()

can_err_count_t CANDeviceManager::clear_errs ( )

virtual

Clear the error counts and return the old counts.

Returns

old counts

get_errs()

can_err_count_t CANDeviceManager::get_errs ( )

virtual

Return the current error count.

init()

void CANDeviceManager::init ( unsigned int  base_address, unsigned int  bit_speed, BYTE  extended_frame  )

virtual

Initialize the Phillips SJA1000 chip to support the CAN.

Parameters

base_address	memory-mapped base address of the CAN registers. Used by the CANin and CANout macros to access registers.
bit_speed	CAN bit speed, in Kb/s
extended_frame	specifies whether the CAN is using the standard or extended frame format

Set up variables used to set up timing and acceptance.

interrupt()

int CANDeviceManager::interrupt ( CircularBuffer *  in_buff, CircularBuffer *  out_buff, can_filter_t  filter  )

virtual

Interrupt Request, ISR

Called by can_handle_interrupt.

Parameters

in_buff	circular buffer for the input messages
out_buff	circular buffer for the output messages
filter	used to set filtering of CAN messages

Returns

1 if the CAN received the interrupt, 0 otherwise

read()

can_msg_t CANDeviceManager::read ( CircularBuffer *  in_buff )

virtual

Read the latest element in the buffer.

This will also remove the element from the buffer.

Parameters

in_buff

circular buffer for the input messages

Returns

the front-most message.

rx_process_interrupt()

void CANDeviceManager::rx_process_interrupt ( CircularBuffer *  in_buff, can_filter_t  filter  )

virtual

Read message from chip and queue for the resource manager.

Parameters

in_buff	circular buffer for the input messages
filter	used to set filtering of CAN messages

send()

void CANDeviceManager::send ( CircularBuffer *  out_buff )

virtual

Send a message to the bus.

Single CAN frames or the very first Message are copied into the CAN controller using this function. After that an transmission request is set in the CAN controllers command register. After a successful transmission, an interrupt will be generated, which will be handled in the CAN ISR CAN_Interrupt().

Parameters

pattr

pointer to information per device manager

tx_process_interrupt()

void CANDeviceManager::tx_process_interrupt ( CircularBuffer *  out_buff )

virtual

Send a new message after notification of transmission of old one.

Parameters

out_buff

circular buffer for the output messages

write()

int CANDeviceManager::write ( CircularBuffer *  out_buff, can_msg_t *  pmsg  )

virtual

Write a new message to the CAN card.

This method is responsible for performing the following tasks.

• If a new message is provided, it is written to and stored in the provided output buffer, tHen promptly sent to the CAN card.
• If no message was sent to the CAN card within the past second (with the assumption that we are sending heartbeat messages at the frequency of 1 Hz), the can_timeout_count attribute is incremented.
• If the buffer has got more than 10 messages stored, the messages are flushed from the system and the number of removed messages is added to the tx_buffer_flush attribute.

Parameters

out_buff	circular buffer that stores output messages
pmsg	pointer to the CAN message that should be written

Returns

0 for success, or -1 if an error occurs

Member Data Documentation

can_notify_client_err

int CANDeviceManager::can_notify_client_err = 0

TODO

can_timeout_count

int CANDeviceManager::can_timeout_count = 0

Number of times a heartbeat was not received from the CAN for over 1 consecutive second.

mask_count_non_zero

int CANDeviceManager::mask_count_non_zero = 0

TODO

tx_buffer_flush

int CANDeviceManager::tx_buffer_flush = 0

Number of messages that were flushed from the output buffer without ever being sent.

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

• include/can/can_man.h
• include/can/can_dev.cpp