need help..
i need an assembly code to check whether a processor is 16 bit or more...
Posted on 2010-07-11 11:31:53 by prasunvelayudhan
Posted on 2010-07-11 12:39:18 by SpooK
ok, so is there a tutorial for checking for 64-bit cpu protected mode support too ;) preferably for nasm, I basically want to make my bootloader only work on 64-bit processors but return an error message if on a 16-bit or 32-bit processor. Also is there a more in-depth tutorial on running 32-bit apps in 64-bit and setting up GDT & IDT with specific reference to changing display modes from within protected mode. TIA
Posted on 2010-08-10 14:52:03 by danielrhodea

ok, so is there a tutorial for checking for 64-bit cpu protected mode support too ;) preferably for nasm, I basically want to make my bootloader only work on 64-bit processors but return an error message if on a 16-bit or 32-bit processor.


Start with the above tutorial link, and follow it up with This OSDev Wiki Article Section.


Also is there a more in-depth tutorial on running 32-bit apps in 64-bit


I'm not aware of any full-out tutorials, but this thread has a few pointers. The Intel/AMD docs are really the "tutorial" you are looking for.


and setting up GDT & IDT with specific reference to changing display modes from within protected mode.


Drawing in Protected Mode @ OSDev.org Wiki

GDT should have nothing to do with it. IDT as well, unless you are talking about some int-based API or odd/old driver design.
Posted on 2010-08-10 15:56:32 by SpooK