Intel 80286, 80287 manual Out Ox,Al, Output byte AL to port number OX, Out Ox,Ax

THE 80286 INSTRUCTION SET

OUT -Output to Port

Opcode		Instruction	Clocks	Description
E6	db	OUT db,AL	3	Output byte AL to immediate port number db.
E7	db	OUT db,AX	3	Output word AX to immediate port number db
EE		OUT OX,AL	3	Output byte AL to port number OX
EF		OUT OX,AX	3	Output word AX to port number OX

FLAGS MODIFIED

None

FLAGS UNDEFINED

None

OPERATION

OUT transfers a data byte or data word from the register CAL or AX) given.as the second operand to the output port numbered by the first operand. You can output to any port from{)-65535 by placing the port number in the DX register then using an OUT instruction with DX as the first operand. If the instruction contains an 8-bit port ID, that value is zero-extended to 16 bits.

Intel reserves I/0 port addresses OOF8H through OOFFH; these addresses should not be used.

PROTECTED MODE EXCEPTIONS

#GP(O) if the current privilege level is bigger (has less privilege) than IOPL, which is the privilege level found in the flags register.

REAL ADDRESS MODE EXCEPTIONS

None

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