CAN errors & Log

Files
file	CO_error.h
	CANopenNode Linux socketCAN Error handling.

Data Structures
struct	CO_CANinterfaceErrorhandler_t
	socketCAN interface error handling More...

Macros
#define	CO_CANerror_NOACK_MAX   16
	This is how many NO-ACKs need to be received in a row to assume that no other nodes are connected to a bus and therefore are assuming listen-only.
#define	CO_CANerror_LISTEN_ONLY   10
	This is how long we are going to block transmission if listen-only mode is active. More...

Enumerations
enum	CO_CANinterfaceState_t { CO_INTERFACE_ACTIVE, CO_INTERFACE_LISTEN_ONLY, CO_INTERFACE_BUS_OFF }
	driver interface state More...

Functions
void	log_printf (int priority, const char *format,...)
	Message logging function. More...
void	CO_CANerror_init (CO_CANinterfaceErrorhandler_t *CANerrorhandler, int fd, const char *ifname)
	Initialize CAN error handler. More...
void	CO_CANerror_disable (CO_CANinterfaceErrorhandler_t *CANerrorhandler)
	Reset CAN error handler. More...
void	CO_CANerror_rxMsg (CO_CANinterfaceErrorhandler_t *CANerrorhandler)
	Message received event. More...
CO_CANinterfaceState_t	CO_CANerror_txMsg (CO_CANinterfaceErrorhandler_t *CANerrorhandler)
	Check if interface is ready for message transmission. More...
CO_CANinterfaceState_t	CO_CANerror_rxMsgError (CO_CANinterfaceErrorhandler_t *CANerrorhandler, const struct can_frame *msg)
	Error message received event. More...

Detailed Description

CANopen Errors and System message log

Macro Definition Documentation

CO_CANerror_LISTEN_ONLY

#define CO_CANerror_LISTEN_ONLY   10

This is how long we are going to block transmission if listen-only mode is active.

Time is in seconds.

Enumeration Type Documentation

CO_CANinterfaceState_t

enum CO_CANinterfaceState_t

driver interface state

CAN hardware can be in the followning states:

• error active (OK)
• error passive (Can't generate error flags)
• bus off (no influence on bus)

Enumerator
CO_INTERFACE_ACTIVE	CAN error passive/active.
CO_INTERFACE_LISTEN_ONLY	CAN error passive/active, but currently no other device on bus.
CO_INTERFACE_BUS_OFF	CAN bus off.

Function Documentation

log_printf()

void log_printf	(	int	priority,
		const char *	format,
			...
	)

Message logging function.

Function must be defined by application. It should record log message to some place, for example syslog() call in Linux or logging functionality in CANopen gateway Gateway ASCII mapping.

By default system stores messages in /var/log/syslog file. Log can optionally be configured before, for example to filter out less critical errors than LOG_NOTICE, specify program name, print also process PID and print also to standard error, set 'user' type of program, use:

setlogmask (LOG_UPTO (LOG_NOTICE));
openlog ("exampleprog", LOG_PID | LOG_PERROR, LOG_USER);

Parameters

priority	one of LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR, LOG_WARNING, LOG_NOTICE, LOG_INFO, LOG_DEBUG
format	format string as in printf

CO_CANerror_init()

void CO_CANerror_init	(	CO_CANinterfaceErrorhandler_t *	CANerrorhandler,
		int	fd,
		const char *	ifname
	)

Initialize CAN error handler.

We need one error handler per interface

Parameters

CANerrorhandler	This object will be initialized.
fd	interface file descriptor
ifname	interface name as string

CO_CANerror_disable()

void CO_CANerror_disable

(

CO_CANinterfaceErrorhandler_t *

CANerrorhandler

)

Reset CAN error handler.

Parameters

CANerrorhandler

CAN error object.

CO_CANerror_rxMsg()

void CO_CANerror_rxMsg

(

CO_CANinterfaceErrorhandler_t *

CANerrorhandler

)

Message received event.

When a message is received at least one other CAN module is connected. Function clears listenOnly and noackCounter error flags.

Parameters

CANerrorhandler

CAN error object.

CO_CANerror_txMsg()

CO_CANinterfaceState_t CO_CANerror_txMsg

(

CO_CANinterfaceErrorhandler_t *

CANerrorhandler

)

Check if interface is ready for message transmission.

Message mustn't be transmitted if not ready.

Parameters

CANerrorhandler

CAN error object.

Returns

CO_INTERFACE_ACTIVE message transmission ready

CO_CANerror_rxMsgError()

CO_CANinterfaceState_t CO_CANerror_rxMsgError	(	CO_CANinterfaceErrorhandler_t *	CANerrorhandler,
		const struct can_frame *	msg
	)

Error message received event.

This handles all received error messages.

Parameters

CANerrorhandler	CAN error object.
msg	received error message

Returns

CO_CANinterfaceState_t