I wonder if there is a difference between

TIMES 33 db 0

and

db 33 dup(0)

revolution wrote:

smiddy: Are you sure that 0x1fe stack is enough? Have you determined why you code failed on loading to 0xf000? I can understand why 0xf800 failed because of stack overwriting but why fail at 0xf000 unless the stack usage is more than 0x800.

It started at SS=0 and SP=0, it decremented towards 0:FFFF, 0:FFFE, ..., 0:F000 or somewhere within that 2048 bytes, I assume. I reverted back from using single sector loads to 32 sectors per load, and that also worked now. I researched the INT 13h Function 42h buffer, and I couldn't find anything to indicate it writes outside of the BIOS area. I will continue to monitor it to see how it goes, but for now it loads my OS and the OS runs as expected (minus the bugs it already had).

edfed wrote:

it looks like a tutorial with all the comments. cool!

That is kind of the plan. My in line with my own learning versus coming back to it many years later. I wrote my OS originally in 2005 and it wasn't much, but now I'm having fits trying to remember what I did and in the places where I didn't comment I am having to relearn it. That's not too bad, because that is the point of what I'm doing, to learn to code and to learn the x86 hardware better. Thanks for the complement!

shutdownall wrote:

I wonder if there is a difference between TIMES 33 db 0 and db 33 dup(0)

Convention? I like the way you did the second one better perhaps, uses less space.