INT 6B - NPC NCSI EXTENDED SERIAL I/O - SET/RETRIEVE VIRTUAL CIRCUIT CONFIG     
	AH = 15h
	AL = virtual circuit number
	CL = direction (00h get, nonzero set)
	ES:BX -> buffer for/containing virtual circuit config (see #03731)
Return: ES:BX buffer filled
Note:	this function is also supported by TelAPI
SeeAlso: AH=13h"NCSI",AH=14h"NCSI"


Format of virtual circuit configuration:
Offset	Size	Description	(Table 03731)
 00h	WORD	buffer length
 02h	WORD	port ID
 04h	WORD	receive rate
 06h	WORD	receive word length
 08h	WORD	receive stop bits
 0Ah	WORD	receive parity
 0Ch	WORD	transmit rate
 0Eh	WORD	transmit word length
 10h	WORD	transmit stop bits
 12h	WORD	transmit parity
 14h	WORD	DTR
 16h	WORD	RTS