Re: A83: Re: weird ROM...
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Re: A83: Re: weird ROM...
It would be very difficult to do so. The original pointers are, of course,
in ROM, so you can't do much with them. The only possibility would be to
have an interrupt that reads key-presses to know when things are going to
happen, and plans accordingly with vector changes and the like. Of course,
you have to worry about all sorts of other things dealing with interrupts in
this case, and I think it's not worth the trouble (and it would be a lot of
trouble).
-Dan Englender
----- Original Message -----
From: "yhean" <yhean@lycos.com>
To: <assembly-83@lists.ticalc.org>
Sent: Monday, January 29, 2001 6:55 PM
Subject: Re: A83: Re: weird ROM...
>
>
> Right, that's my problem since the TI-OS rebuilds the table every time the
user "does something".
> So I started looking for the originals pointers, but I know I cannot
change them... so do you think it is possible, in any way, on the TI-83, to
install hooks?
> I have been trying for a month but I have not been able to find a correct
(working) way yet.
>
> Jean Carot
>
>
> --
>
> On Mon, 29 Jan 2001 16:34:57
> Dan Englender wrote:
> >
> >Well, if you change the vectors to point to some code you want it to
> >execute, it should work. The problem is that's it's not easy to get the
> >points you want in there. TIOS changes the vectors itself whenever an
> >application change occurs, so if you change the vectors in an assembly
> >program (which has a specific context), the vectors will be overwritten
when
> >you quit and return to the homescreen context. On the TI-83 Plus, this
is
> >facilitated slightly because there are built in hooks in many of the TIOS
> >application main routines.
> >
> >-Dan Englender
> >
> >----- Original Message -----
> >From: "yhean" <yhean@lycos.com>
> >To: <assembly-83@lists.ticalc.org>
> >Sent: Monday, January 29, 2001 3:43 PM
> >Subject: Re: A83: Re: weird ROM...
> >
> >
> >>
> >>
> >> About these vectors, do you think it is possible to bypass them, so you
> >can install a "hook" ?
> >> This was my initial search, but I don't think this vector table is
> >usable...
> >>
> >> Jean
> >>
> >>
> >> --
> >>
> >> On Sun, 28 Jan 2001 23:02:01
> >> Dan Englender wrote:
> >> >
> >> >I think you've got a couple different issues here. First, on the
seven
> >> >pointers plus backups, it sounds like you're talking about the system
> >> >monitor vectors. Actually, there are only six of these vectors. The
> >last
> >> >two bytes in the table are the page of the current application, and
the
> >> >context number of the current application. These vectors are used by
the
> >> >TIOS to pass information to the currently running application. Check
my
> >> >"A83: Re: ROMcall reference" from the yesterday (the 27th) for more
> >> >information on these vectors.
> >> >
> >>
> >>
> >>
> >> Get your small business started at Lycos Small Business at
> >http://www.lycos.com/business/mail.html
> >>
> >
> >
> >
>
>
> Get your small business started at Lycos Small Business at
http://www.lycos.com/business/mail.html
>
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