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 boot loader 
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Joined: Fri Aug 20, 2010 10:04 pm
Posts: 41
Post boot loader
Here's my boot loader:

http://www.losethos.com/code/BootHD.html

I didn't know there was a standard address of 0x7C00 when I wrote it, so I made it work for any load address. It copies itself up to just under 0x80000, then loads the 2nd stage to 0x10000.

Before I made a boot loader, I launched my kernel from real mode FREEDOS. It started like an application and because free dos lets you do anything, I had access to GDT and could just switch-over to protected mode. I remember it used to load it to an unusual address because it was an application.


I wrote my own assembler and didn't bother with all the 16-bit code modes that are not used in 64-bit mode. Therefore, I hand code a far jump instruction.


Sat Jan 08, 2011 11:53 pm
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Joined: Fri Jul 24, 2009 10:02 pm
Posts: 247
Location: Las Vegas, NV, US
Post Re: boot loader
Love the syntax highlighting! Thanks for sharing...


PS - is your screenname a reference to Greek for God? Hehe.


Mon Mar 07, 2011 5:11 am
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