Re: A82: Pointers and shells

To: assembly-82@lists.ticalc.org
Subject: Re: A82: Pointers and shells
From: Matt Maurano <maurano@best.com>
Date: Thu, 06 Nov 1997 17:48:43 -0800
Organization: Whatzever
References: <21660790.34626b49@aol.com>
Reply-To: assembly-82@lists.ticalc.org

To run Zshell, Ash, or Fargo, a bug/flaw is taken advantage of to trick the
calculator into running assembly code from a predeterminied location in memory.

prgmABC is not a pointer to ABS, but exactly what you see there. When the calc
sees "prgm", it thinks, "What comes next is the name of the program to
interpret". It then loads that program, "ABC" into some code that will
translate BAsic into assembly. Basically, it would not work unless TI made
major errors when programming.

GeradS711 wrote:

> I was reading up about assembly and how the shells are made and I learned
> that somehow a line of calculations or something is a pointer to the ram.
> Anyway, could someone clarify this for me. Also if this is true, then
> wouldn't a line of code in a program contain a pointer to a different place
> in the RAM?? For example doing this in TI-Basic would contain a pointer to
> the location of program abc in the ram
> :prgmABC
> Could this pointer be ajusted so that it would execute the assembly
> thingy-bober? This would be very cool because it would do two things.
> 1) eliminate the "PRESS ENTER" before a shell, or program, is executed
> and
> 2) make it possible to interlace TI-Basic and Asm programs like the 83.
> Just wondering if it is possible, because I have no where near the
> programming knowledge to try and do something like that.:-)

References:

A82: Pointers and shells

From: GeradS711 <GeradS711@aol.com>