INT 2F U - TeleReplica - INSTALLATION CHECK                                     
	AX = D300h
	BX = 4562h
	CX = 2745h
	DX = serial port I/O base address??? (03F8h for v3.9)
Return: SI = segment of resident code
	AX = 251Dh
	BX = DF21h
	CX = F321h
	DX = ???