Re: A89: Re: Re: Re: ASM without libraries
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Re: A89: Re: Re: Re: ASM without libraries
> >
> > > ok.. the thing was just that old plusshell attached a 900bytes or so
> loader.
> >
> > OK, now I get what you meant.
> >
> > > the kernel handles romcalls? why should it interfere with that?
> >
> > Not the romcalls themselves, but the relocation of them (keeps them in a
> list
> > similar to the library calls and replaces them with the appropriate
> address when
> > relocated).
> >
>
> Could you please explain this to me -- it's one of those things that I don't
> understand that just keeps haunting me. The ROM is never relocated, right?
> So all addresses ROM functions could be inserted at compile time, right?
> How is relocation involved then? Why does the program's location in memory
> affect how ROM functions are called? Do JSR's/BSR's use relative addresses
> or something?
They could be inserted at compile time... but then the program would only work
on one ROM version, and, in the case of the 89 and 92+ (which have the same ROM
functions), only one calculator model. The whole point with the ROM call table
is to provide compability between different versions.
/ Niklas Brunlid
Check out Prosit for the TI-89 / TI-92 Plus at http://c625.sparta.lu.se
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