INT 14 - MultiDOS Plus - INITIALIZE PORT AH = 20h AL = port parameters (see AH=00h"SERIAL") DX = port number (0-3) Return: AH = status 00h successful 41h no such port 64h monitor mode already active SeeAlso: AH=04h"MultiDOS",AH=21h"MultiDOS",AH=23h"MultiDOS"