when cpu execute first instruction at 0xF00:0xFFF0, what is the state of registers?
ok, CS is 0xF000, and IP is 0xFFF0.
what about rest?

im disassembling my bios, and finst instruction is mov al,0xE8
second is stos
what is under es and di?
third instruction is indirect far call.
call. what is sp and sp?


HELP ME PLZ!

http://docs.huihoo.com/help-pc/misc-cold_boot.html

i think di is set to 0 too, the first thing done before anything is IVT initialisation.

http://www.intel.com/products/processor/manuals/

Download volume 3A an read chapter 9. But for a quick answer, EDI, EBP and ESP are zero (volume 2 of AMD says the same but for RDI, RBP and RSP).

thx.
so its in manuals? i didnt know.

what about stack? does 0 is a valid address for top of stack?

I think this Q should be added to the FAQ. Many people seem to ask this.

The answer is yes. And it is really easy to test for oneself if one wants to be sure.