Re: LLDT, LGDT/LIDT, SGDT, SIDT, SLDT Instructions

> Anyone here that might have used the following instructions...
> LLDT, LGDT/LIDT, SGDT, SIDT, SLDT
>
> 1) Is there a good description anywhere ?
Try the 80386 programmer's reference manual, or any of the newer versions
from Intel.

> 2) When and/or how might these instructions be used ?
These are used by the lowest routines of the operating system. Often only at
initialization.

> 4) Are they actual registers ?
Yes, all data that the CPU needs to operate are accessed via these
registers.

> 5) Anyone have a list of which processors support these
> instructions ?
All CPUs who supports protected mode, starting from the 80286 (made in
1982).


H


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