Protected Mode Keyboard Access on x86 Assembly -

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i'm working on keyboard input basic kernel i'm developing , i'm stuck. can't seem find information online can show me information need know.

my kernel running in protected mode right now, can't use real mode keyboard routines without jumping real mode , back, i'm trying avoid. want able access keyboard protected mode. know how this? thing have found far involves talking controller directly using in/out ports, beyond i'm stumped. is, of course, not comes often. normally, assembly tutorials assume you're running operating system underneath.

i'm new x86 assembly, i'm looking resources working standard hardware protected mode. i'm compiling assembly source code nasm , linking c source code compiled djgpp. suggestions?

the mit operating systems class has lots of references. in particular, check out adam chapweske's resources on keyboard , mouse programming.

in short, yes, using raw in/out ports, requires either running in kernel mode, or having i/o permission bits (iopl) set in eflags register. see this page more details on i/o permissions.


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