TIME

CANopen Time-stamp protocol. More...

Collaboration diagram for TIME:

Files
file	CO_TIME.h
	CANopen Time-stamp protocol.

Data Structures
struct	CO_TIME_t
	TIME producer and consumer object. More...

Macros
#define	CO_TIME_MSG_LENGTH   6U
	Length of the TIME message.

Functions
CO_ReturnError_t	CO_TIME_init (CO_TIME_t *TIME, OD_entry_t *OD_1012_cobIdTimeStamp, CO_CANmodule_t *CANdevRx, uint16_t CANdevRxIdx, CO_CANmodule_t *CANdevTx, uint16_t CANdevTxIdx, uint32_t *errInfo)
	Initialize TIME object.
void	CO_TIME_initCallbackPre (CO_TIME_t *TIME, void *object, void(*pFunctSignalPre)(void *object))
	Initialize TIME callback function.
static void	CO_TIME_set (CO_TIME_t *TIME, uint32_t ms, uint16_t days, uint32_t producerInterval_ms)
	Set current time.
bool_t	CO_TIME_process (CO_TIME_t *TIME, bool_t NMTisPreOrOperational, uint32_t timeDifference_us)
	Process TIME object.

Detailed Description

CANopen Time-stamp protocol.

For CAN identifier see Default CANopen identifiers

TIME message is used for time synchronization of the nodes on the network. One node should be TIME producer, others can be TIME consumers. This is configured by COB_ID_TIME object 0x1012:

• bit 31 should be set for a consumer
• bit 30 should be set for a producer
• bits 0..10 is CAN-ID, 0x100 by default

Current time can be read from CO_TIME_t->ms (milliseconds after midnight) and CO_TIME_t->days (number of days since January 1, 1984). Those values are updated on each CO_TIME_process() call, either from internal timer or from received time stamp message.

Current time can be set with CO_TIME_set() function, which is necessary at least once, if time producer. If configured, time stamp message is send from CO_TIME_process() in intervals specified by CO_TIME_set()

Function Documentation

CO_TIME_init()

CO_ReturnError_t CO_TIME_init	(	CO_TIME_t *	TIME,
		OD_entry_t *	OD_1012_cobIdTimeStamp,
		CO_CANmodule_t *	CANdevRx,
		uint16_t	CANdevRxIdx,
		CO_CANmodule_t *	CANdevTx,
		uint16_t	CANdevTxIdx,
		uint32_t *	errInfo )

Initialize TIME object.

Function must be called in the communication reset section.

Parameters

	TIME	This object will be initialized.
	OD_1012_cobIdTimeStamp	OD entry for 0x1012 - "COB-ID time stamp", entry is required.
	CANdevRx	CAN device for TIME reception.
	CANdevRxIdx	Index of receive buffer in the above CAN device.
	CANdevTx	CAN device for TIME transmission.
	CANdevTxIdx	Index of transmit buffer in the above CAN device.
[out]	errInfo	Additional information in case of error, may be NULL.

Returns

CO_ReturnError_t CO_ERROR_NO on success.

CO_TIME_initCallbackPre()

void CO_TIME_initCallbackPre	(	CO_TIME_t *	TIME,
		void *	object,
		void(*	pFunctSignalPre )(void *object) )

Initialize TIME callback function.

Function initializes optional callback function, which should immediately start processing of CO_TIME_process() function. Callback is called after TIME message is received from the CAN bus.

Parameters

TIME	This object.
object	Pointer to object, which will be passed to pFunctSignalPre().
pFunctSignalPre	Pointer to the callback function. Not called if NULL.

CO_TIME_set()

static void CO_TIME_set ( CO_TIME_t * TIME, uint32_t ms, uint16_t days, uint32_t producerInterval_ms )

inlinestatic

Set current time.

Parameters

TIME	This object.
ms	Milliseconds after midnight
days	Number of days since January 1, 1984
producerInterval_ms	Interval time for time producer in milliseconds

CO_TIME_process()

bool_t CO_TIME_process	(	CO_TIME_t *	TIME,
		bool_t	NMTisPreOrOperational,
		uint32_t	timeDifference_us )

Process TIME object.

Function must be called cyclically. It updates internal time from received time stamp message or from timeDifference_us. It also sends produces timestamp message, if producer and producerInterval_ms is set.

Parameters

TIME	This object.
timeDifference_us	Time difference from previous function call in [microseconds].
NMTisPreOrOperational	True if this node is NMT_PRE_OPERATIONAL or NMT_OPERATIONAL state.

Returns

True if new TIME stamp message recently received (consumer).