Online HelpPC 2.10 Quick Reference Utility Copyright 1991 David Jurgens
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
- see Instruction Timing
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