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OUT             Output to Port                       Flags: Not altered

OUT port,accumulator                                 IOpm

        Logic   [port] . accumulator

    OUT transfers a byte, a word, or a doubleword from the accumulator
    (AL, AX, or EAX) to a specified port. The port number is specified
    as an immediate byte value (for ports 0 thru 255) or by the DX
    register (allowing access to all ports).
    If the instruction contains an 8-bit port ID, that value is zero-
    extended to 16 bits.


    Protected mode
    An exception occurs if the current task has insufficient privilege
    for the I/O. OUT is not IOPL-sensitive in V86 mode.


    Note
    I/O ports F8h through FFh are reserved by Intel.


    Opcode      Format
    E6 ib       OUT  imm8,AL
    E7 ib       OUT  imm8,AX
    E7 ib       OUT  imm8,EAX
    EE          OUT  DX,AL
    EF          OUT  DX,AX
    EF          OUT  DX,EAX


    Length and timing
    Operands    Bytes   8088    186     286     386     486     Pentium
    imm8, al     2      14       9       3      10      16      12   NP
    imm8, ax     2      14       9       3      10      16      12   NP
    imm8, eax    2       -       -       -      10      16      12   NP
    dx, al       1      12       7       3      11      16      12   NP
    dx, ax       1      12       7       3      11      16      12   NP
    dx, eax      1       -       -       -      11      16      12   NP

                             Protected Mode

    Operands    Bytes                           386     486     Pentium
    imm8, acc    2                            4/24/24 11/31/29 9/26/24 NP
    dx, acc      1                            5/25/25 10/30/29 9/26/24 NP

               Cycles for: CPL <= IOPL / CPL > IOPL / V86