ticks_since_event

	ticks_since.i4.v = ticks_since_event(event.i4.v)

	This routine returns the number of 15 Hz ticks since the specified 
	event last occurred.  If the event has never been seen on this node,
	a -1 is returned.

	event		clock event number as follows:
			  0 -  255	event 0 - 255 of the clock specified
   	    	    	by Default Clock in the Utilities Window or the most
   	    	    	recent call to clock_set_multicast_type.
   	    	    	  0 - 255 + TCLK_BASE	    	TCLK event 0 - 255
   	    	    	  0 - 255 + MIBS_BASE	    	MIBS event 0 - 255
   	    	    	  0 - 255 + RRBS_BASE	    	RRBS event 0 - 255
   	    	    	  0 - 255 + TVBS_BASE	    	TVBS event 0 - 255
   	    	    	  0 - 255 + TESTCLK_BASE    	TEST clock event 0 - 255
   	    	    	  0 - 255 + PROJCLK_BASE    	PROJ clock event 0 - 255
   	    	    	  0 - 255 + NMLCLK_BASE     	NML clock event 0 - 255
			(constants are in 'tclk_events')

	This function returns status values as follows:

	ticks_since	number of 15Hz ticks since the event last occurred or -1

	This function requires the following include files:

	clib_h, tclk_events_h

	Related functions:

	evmon, evmon_usec_c, lckclk_c, lckclk_api, lckclk_allocate,
	lckclk_free, acctim, event_history, event_set_fake, reflected_events_c
	clock_set_multicast_type, clock_get_default_multicast_type,
	event_translate_c, event_count_c, event_last_timestamp_c,
	clock_type_convert_c, is_beam_sync_clock_type_c

	C/C++ usage:

	int	ticks_since;
	int	event = EVENT_MI_RESET_FIXED_TARG;

	ticks_since = ticks_since_event(event);