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  Interrupt:   14h     Function:   00h
 
  Title:       Initialize Communications Port
 
  Description:                                          [PC] [AT] [PS/2]
 
     Initializes a serial communications port to a desired baud rate,
     parity, word length, and number of stop bits.
 
     Input                        Output
 
     AH = 00h                     AH = Port status
     AL = Initialization
          parameter               Bits   Significance (if set)
     DX = Communications
          port number             7      Timed-out
          (0 = COM1,              6      Transmit shift
          1 = COM2,...)                  Register empty
                                  5      Transmit holding
                                         Register empty
                                  4      Break detected
                                  3      Framing error detected
                                  2      Parity error detected
                                  1      Overrun error detected
                                  0      Receive data ready
 
                                  AL = Modem status
 
                                  Bits   Significance (if set)
 
                                  7      Receive line signal
                                         detect
                                  6      Ring indicator
                                  5      Data-set-ready
                                  4      Clear-to-send
                                  3      Change in receive line
                                         signal detect
                                  2      Trailing edge ring
                                         indicator
                                  1      Change in
                                         data-set-ready status
                                  0      Change in
                                         clear-to-send status
                                    -♦-