OUT              Output to Port                      Flags: not altered

OUT port,accumulator

Logic:    (port)   accumulator

OUT transfers a byte or a word from AL or AX to the specified port.

The port may be specified with an immediate byte constant (allowing

access to ports 0 through 255) or with a word value in DX (allowing

access to ports 0 through 65,535).

Operands                  Clocks   Transfers  Bytes   Example

                        byte(word)

immed8, accumulator       10(14)       1        2     OUT 254,AX

DX, accumulator           8(12)        1        1     OUT DX,AL

Note:          It is advised that hardware not use I/O ports F8h

through FFh, since these are reserved for

controlling the math coprocessor and future

processor extensions.

Prev:     OR Logical OR

See also: IN

Next:     POP Pop a Word from the Stack