Bona Fide OS Development update(June 4)

[K.J. aka osmaker]

June 4, 2002

    * Added a several new tutorials in the Tutorials & Docs section
    * Removed the Very Basic PMode tutorial as it doesn't really switch to PMode(thanks go to Tim Robinson for pointing this out)
    * Added a few new links
* The downloads section will be back up as soon as I have the time to rebuild it's structure

http://osdev.redir.net

K.J. aka osmaker

[Ben Hsu]

Are you sure that the "Very Basic PMode" tutorial doesn't work?  Because I've tried the code with Bochs with a little more complete parts and it actually entered Pmode when I check the Bochs debug output..., see I now remember maybe a few tweeking and it'll work...but don't remember exactly what i did..

Ben Hsu

[Tim Robinson]

It enters protected mode in the sense that it sets the PE bit in CR0, but it stays in real mode in the sense that it doesn't load a protected-mode descriptor into CS. In fact, this is closer to unreal mode: if you made up a GDT with a flat data descriptor and loaded DS with a flat selector, you could access 4GB of memory from real mode (i.e. unreal mode). But it's not true protected mode until you've loaded CS with a code descriptor.

[Ben Hsu]

yeah, i'm implementing the descriptors and their tables so it will become true Pmode.

Ben Hsu