>but what is "unreal" mode,
In a nutshell:
You enter pmode, change the lengths of the
descriptors to 4GB (or whatever) and jmp
back to real mode... the segment lengths stay the
same, so you've got access to all your memory...
no protection, and no native 32-bit code though.
I wouldn't reccomend it.
>and virtual 86 mode?
Used in pmode to "emulate" x86 programs with
protection schemes implemented. Usually used to
emulator binaries from other operating systems.
It's very much like a debugger, actually.
>About the interrupts. I haven't found a lot of info
>on custom interrupts. I would like to have interrupts
>much like DOS, one for the disk, one for programs, a
>main system call, etc. How can I write my own interrupt
>handler for interrupts 20 through 25 or so?
You mean 0x20? I wouldn't reccoment 20... might
still conflict with hardware interrupts (?)
I'd also reccomend remapping (using CR3, and the
paging system) the operating system functions
into the users address space so they can, more or
less, call OS functions directly, not through
interrupts... might be faster... don't know how
well protection can be implemented, though.
>
>Any help is appreciated. Thanks people!
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