Re: A83: Has anyone dumped the 83+ ROM?
[Prev][Next][Index][Thread]
Re: A83: Has anyone dumped the 83+ ROM?
See Inside...
In a message dated 9/25/99 1:29:21 AM Central Daylight Time,
barubary@home.com writes:
> > Well lets see... Yes FlashRom is in $4000-$7FFF most of the time, unless
> you
> > manually switch a Ram page into there for some odd reason... Where do you
> > plan on "finding out" if an application can do this for you? An 83 Emu
on
> > the 83+ is really a dumb idea... It's not worth it to try to fit the 83's
> Rom
> > into Archive Memory on the 83+, and then have some type of program that
> > redirects alot of romcalls in the 83 prog's data... It's just easier to
> write
> > for ION, and then your progs become compatible for the 83 and 83+, and
> games
> > can be ported quite easily also... Btw, its not like there is some big
> > secret, or that there is some hidden info out there that will allow you
to
> > better create this idea which many other people have brainstormed for, it
> is
> > just not proctical to try to get 83 games to run on the 83+ without any
> > alteration... Oh yeah, and about the rom dump, no, nobody has gotten one
> for
> > the 83+ yet... cya. =P
>
> Umm... you could just redirect the jump table only.
How do you plan to do that? I'm interested... =)
> Here's why I don't use ION: squish.inc is HUGE compared to ion.inc.
Do you prefer squish.inc because of its physical size compared to ion.inc?
about 3/4ths of the romcalls in there arent even used or purposeful to asm
programmers, and most of squish.inc is because it contains every token and
character that is used on the calc, and ion.inc doesnt...
If you make this statment comparing the amount of documentation there is for
the 83+, then you are mistaken... there has been more information released to
people who make applications for the 83+, this just isnt freely released to
the public, and dont go around asking people for it, because they could get
sued by TI for destributing anything. Also, what we do have is still not
much. TI are bastards for giving us hardly any documentation for romcalls,
and even less entry points to the system routines for use to figure them out
ourselves... so, its TI's fault we dont know enough about the 83+ yet... =P
> As for the alteration problem... Since the shell would be forced to be 16k
> long, I might as well add code to the shell to recognize games and patch
> them accordingly. This would have to be done for games like Penguins,
which
> accesses the VAT directly (as the 83+ has a different format). CrASH was
> 1000 bytes and had excellent features - imagine what could be done with
8000
> (4000-5FFF would be mostly taken by the massive jump table for 83 support.)
Alright, that is a good point you realize... games would have to be patched
for many things, such as all the various Ram Location Differences that are on
the 83+ compared to the 83. Also, the memory location for the place where asm
programs execute, is different than on the 83. This would require the
shell/emu thing to alter the program directly when it is executed on the
calc, and change Every user defined variable equate, and Every jump and call
address to routines throughout the program. That is far too much effort, and
you are doing most things that could be changed in the source and recompiled
for the 83+ anyways...
> Another thing I plan on doing for the 83+ is cracking the digital signing.
> TI is not going to use any sort of digital signing that prohibits
> exportation of 83+'s...
I dont beleive that TI is our enemies for doing this. they were very logical
to put in all the security for the flashrom, and smart on how they did it i
might add. I assume that it will be hard to crack any encryption they use
since on the 89, i heard theyve used 512 bit encryption (whatever that means,
i dont know) but i know its alot, or hard to decrypt. and the 83+ was
developed after the 89, so the same processes for security, if not better,
have been implemented...
> How is it that ION has control over the flashrom? A ROM dump MUST exist
for
> someone to reverse THAT...
>
> -- Barubary
You refer to the fact that ION can run programs that are located in flashrom.
That is easily done with a romcall that TI has actually provided us with, to
Archive/Unarchive FlashRom variables. Joe has to move the program to Ram
before being able to execute it, and that is why you may notice that archived
programs take longer to load when you run them from the shell...
Alright, well what else do you have up your sleave that you think you can do
to make the 83+ emulate 83 games? I'll try to provide the discouraging answer
to it early, so you dont waste your time on something like this. By the facts
you present though, it sounds like you are adept to asm, and maybe your
efforts can be put to something more practical, thats all im saying... cya.
Jason_K