Re: A83: Re: weird ROM...


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Re: A83: Re: weird ROM...




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
>




References: