OUT - Output Data to Port

        Usage:  OUT     port,accum
        Modifies flags: None

        Transfers byte in AL,word in AX or dword in EAX to the specified
        hardware port address.  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

        immed8,accum    10/14   3     10     16           2
        immed8,accum (PM) -     -    4/24 11/31/29        2
        DX,accum         8/12   3     11     16           1
        DX,accum (PM)     -     -    5/25 10/30/29        1

        - 386+ protected mode timings depend on privilege levels.

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

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