OUT
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.
Output Data to I/O Port
OUT imm8,AL ; E6 ib [8086]
OUT imm8,AX ; o16 E7 ib [8086]
OUT imm8,EAX ; o32 E7 ib [386]
OUT DX,AL ; EE [8086]
OUT DX,AX ; o16 EF [8086]
OUT DX,EAX ; o32 EF [386]
OUT writes the contents of the given source register to the specified I/O port. The port number may be specified as an immediate value if it is between 0 and 255, and otherwise must be stored in DX. See also IN.
Example:
out 15 eax