INT 14 - MBBIOS - INITIALIZE PORT
        AH = 00h
        AL = port parameters
            bits 7-5 data rate
                        (normally 110,150,300,600,1200,2400,4800,9600 bps;
                        9600,14400,19200,28800,38400,57600,115200,330400 bps
                        if the high-speed option is set)
            bits 4-3 parity (00 or 10 = none, 01 = odd, 11 = even)
            bit 2    stop bits (set = 2, clear = 1)
            bits 1-0 data bits (00 = 5, 01 = 6, 10 = 7, 11 = 8)
        DX = port number
Return: AH = line status (see AH=03h)
        AL = modem status (see AH=03h)
Note:   MBBIOS was written by H. Roy Engehausen
SeeAlso: AH=05h"MBBIOS"