On Fri, Jul 16, 2004 at 12:32:24AM +0400, breath probably wrote: > Normal: > When you boot from the floppy you get something like black screen and > computer hangs up (but not reboots) > > Abnormal: > When you boot from the floppy you get a screen splash and then back to > reboot POST procedure.
Heh. The only thing I can think of right now is an interrupt not masked by the cli you issued. You could try inserting a `mov ss, something' just before the jump. This will prevent any processor from doing any interrupts, as the immediately next instruction should be `mov sp, something' (it was documented somewhere). Like > mov eax, cr0 > or al, 0x1 ; cr0 |= PE mov dx, 0x8 > mov cr0, eax mov ss, dx > jmp 0x10: protected <snip> > .gdt0 dw 0x0000, 0x0000, 0x0000, 0x0000 > .data dw 0xFFFF, 0x0000, 0x9200, 0x00CF > .code dw 0xFFFF, 0x0000, 0x9800, 0x00CF > .gdtr dw $ - .gdt0 - 1 And why `-1'? > dd .gdt0 You could also try adding CPUID's between all instructions for synchronization, in case it's that kind of issue. > Here goes the code. PLEASE, even if you're not interested in this > 'puzzle':( MAKE AND TEST IT ON YOUR COMPUTER. EMAIL ME RESULTS AND > COMPUTER MODEL. As soon as I have access to the 'puter with nasm, maybe. P.S. Does booting DOS, and running a DOS-extended program succeed or fail? -- DoubleF New York is real. The rest is done with mirrors.
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