)
Call NESL function EventNotification with:
	BX = 0003h
	ES:SI -> PECB previously registered (see #03021)
Return: AX = completion code (0h, 8005h, 8008h) (see #03019)
	ES:SI -> still points to PECB
	BP,DS,STACK preserved
Desc:	Allows a module to signal that an event has just occurred in a given
	  event class.
Notes:	Once called, NESL will generate corresponding callouts for this
	  event, as described in Table #03023.
	on entry, the PECB_DataPtr must point at an Event Parameter Block (EPB)
	  (see #03024) filled in to match the desired event
SeeAlso: #03014