INT 6B - Novell NASI/NACS, Ungermann-Bass Net One SERIAL I/O - GET STATUS       
	AX = 0700h
Return: CH <> 00h if connection active
Notes:	this function is also supported by TelAPI and NPC NCSI
	Novell TelAPI returns CX=FF01h and CF clear
SeeAlso: AH=02h,AH=10h