INT 14h,  00h (00)       Initialize Serial Port Parameters

    Initializes the baud rate, parity, stop-bit, and word length
    parameters for a serial port, and returns the status for the port.

       On entry:      AH         00h
                      AL         Communications parameters (see below)
                      DX         Serial port number (0 - COM1, 1 - COM2, etc.)

       Returns:       AX         Line and modem status (see Service 03h)

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           Baud rate           Parity           Stop bits      Word Length
   Bit:    7 6 5               4 3              2              1 0
           0 0 0    110        0 0  None        0  One         1 0  7 bits
           0 0 1    150        0 1  Odd         1  Two         1 1  8 bits
           0 1 0    300        1 0  None
           0 1 1    600        1 1  Even
           1 0 0  1,200
           1 0 1  2,400
           1 1 0  4,800
           1 1 1  9,600