OUTS - Output String to Port  (80188+)

        Usage:  OUTS    port,src
                OUTSB
                OUTSW
                OUTSD   (386+)
        Modifies flags: None

        Transfers a byte, word or doubleword from src to the hardware
        port specified in DX.  For instructions with no operands the src
        is located at DS:SI and SI is incremented or decremented by the
        size of the operand or the size dictated by the instruction format.
        When the Direction Flag is set SI is decremented, when clear, SI is
        incremented.  If the port number is in the range of 0-255 it can
        be specified as an immediate.  If greater than 255 then the port
        number must be specified in DX.  Since the PC only decodes 10 bits
        of the port address, values over 1023 can only be decoded by third
        party vendor equipment and also map to the port range 0-1023.

                                 Clocks                 Size
        Operands         808x  286   386    486         Bytes

        port,src          -     5     14     17           1
        port,src (PM)     -     -    8/28 10/32/30        1

        - 386+ protected mode timings depend on privilege levels.

          first number is the timing when:    CPL ó IOPL
          second number is the timing when:   CPL > IOPL
          third number is the timing when:    virtual mode on 486 processor


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