Hello!
> > > scan: movw %cs, %ax
> > > movw %ax, %ds
> > > movw %ax, %es
> > > movw $where_in_BIOS_to_start, %bx
> > > cld
> > > 1: movw $cl_id_str, %si # Offset of search string
> > > movw $cl_id_end, %cx # Offset of string end + 1
> > > subw %si, %cx # String length
> > > decw %cx # Don't look for the \0
> > > movw %bx, %di # ES:DI = where to look
> > > repz cmpsb # Loop while the same
> > > jz found # Found the string
> > > incb %bx # Next starting offset
> > > cmpb $_BIOS_END, %bx # Check for limit
> > > jb 1b # Continue
> > > never_found_anywhere:
> > >
> > > found:
> >
> > I've written something similar to this before - and it wont' work, so
> > I've reimplemented it. The problem is, that I don't know how to set ES
> > properly. I only know, that BIOS data (and code) is located in
> > 0xe000..0xf000 (real address).
>
> Yeah. So. I set ES and DS to be exactly where CS is. This means that
> if your &!)(^$&_ code executes it will work. So, instead of trying
> it, you just blindly ignore it and state that it won't work.
>
> Bullshit. I do this for a living and I gave you some valuable time
> which you rejected out-of-hand. Have fun.
Of course, I've tried your code as well - the same result! Sorry, if you
haven't understand me.
The problem is, that I don't know where this BIOS code is relative to current
code segment (CS). I only know (hope), that it should be in
0x0:0xe000...0x0:0xf000. I have tried to set ES to 0 (xor %ax, %ax; mov %ax,
%es) - no luck as well. BTW, `strings /dev/mem | grep "REQUESTED STRING"`
founds it perfectly...
Best regards,
Andrew.
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This archive was generated by hypermail 2b29 : Wed Apr 23 2003 - 22:00:37 EST