TIME

Files
file	CO_TIME.h
	CANopen Time-stamp protocol.

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

Functions
CO_ReturnError_t	CO_TIME_init (CO_TIME_t *TIME, CO_EM_t *em, CO_SDO_t *SDO, CO_NMT_internalState_t *operatingState, uint32_t COB_ID_TIMEMessage, uint32_t TIMECyclePeriod, CO_CANmodule_t *CANdevRx, uint16_t CANdevRxIdx, CO_CANmodule_t *CANdevTx, uint16_t CANdevTxIdx)
	Initialize TIME object. More...
void	CO_TIME_initCallbackPre (CO_TIME_t *TIME, void *object, void(*pFunctSignalPre)(void *object))
	Initialize TIME callback function. More...
uint8_t	CO_TIME_process (CO_TIME_t *TIME, uint32_t timeDifference_us)
	Process TIME communication. More...

Detailed Description

CANopen Time-stamp protocol.

For CAN identifier see CO_Default_CAN_ID_t

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

• bit 31 should be set for a consumer
• bit 30 should be set for a producer

TIME CONSUMER

CO_TIME_init() configuration :

• COB_ID_TIME : 0x80000100L -> TIME consumer with TIME_COB_ID = 0x100
• TIMECyclePeriod :
  • 0 -> no EMCY will be transmitted in case of TIME timeout
  • X -> an EMCY will be transmitted in case of TIME timeout (X * 1.5) ms

Latest time value is stored in CO->TIME->Time variable.

TIME PRODUCER

CO_TIME_init() configuration :

• COB_ID_TIME : 0x40000100L -> TIME producer with TIME_COB_ID = 0x100
• TIMECyclePeriod : Time transmit period in ms

Write time value in CO->TIME->Time variable, this will be sent at TIMECyclePeriod.

Function Documentation

CO_TIME_init()

CO_ReturnError_t CO_TIME_init	(	CO_TIME_t *	TIME,
		CO_EM_t *	em,
		CO_SDO_t *	SDO,
		CO_NMT_internalState_t *	operatingState,
		uint32_t	COB_ID_TIMEMessage,
		uint32_t	TIMECyclePeriod,
		CO_CANmodule_t *	CANdevRx,
		uint16_t	CANdevRxIdx,
		CO_CANmodule_t *	CANdevTx,
		uint16_t	CANdevTxIdx
	)

Initialize TIME object.

Function must be called in the communication reset section.

Parameters

TIME	This object will be initialized.
em	Emergency object.
SDO	SDO server object.
operatingState	Pointer to variable indicating CANopen device NMT internal state.
COB_ID_TIMEMessage	Should be intialized with CO_CAN_ID_TIME_STAMP
TIMECyclePeriod	TIME period in ms (may also be used in consumer mode for timeout detection (1.5x period)).
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.

Returns

CO_ReturnError_t: CO_ERROR_NO or CO_ERROR_ILLEGAL_ARGUMENT.

CO_TIME_initCallbackPre()

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

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(). Can be NULL
pFunctSignalPre	Pointer to the callback function. Not called if NULL.

CO_TIME_process()

uint8_t CO_TIME_process	(	CO_TIME_t *	TIME,
		uint32_t	timeDifference_us
	)

Process TIME communication.

Function must be called cyclically.

Parameters

TIME	This object.
timeDifference_us	Time difference from previous function call in [microseconds].

Returns

0: No special meaning.

1: New TIME message recently received (consumer) / transmited (producer).