A86: Re: ti82/85 emulation like rascall


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A86: Re: ti82/85 emulation like rascall




LOL, a 5 line question that probably requires a 1000 line answer =)

Anyway, a VERY BRIEF summary is that the shell uses page 1 to create a
simulated TI-85 (since the TI-85's sys vars start at $8000 instead of
$C000). You must simulate all ZShell/Usgard/etc ROM calls in this area.
Also, you must search through the code (I prefer a code tracer) and replace
all calls to areas less than $8000, since these are ROM calls and have
changed between 85 and 86. A similar procedure goes for 82.

Now this isn't going to work for programs > 12kb. In order to get programs >
12kb to work, you need to do some other things. YAS for example creates a
space from $8000-$FFFF that simulates the TI-85, and saves the 86's system
vars somewhere secret so that they can be restored. This is VERY
complicated, and I recommend you get < 12kb programs working first before
even thinking about trying > 12kb...

----- Original Message -----
From: jimi malcolm <malcolmj1@juno.com>
To: <assembly-86@lists.ticalc.org>
Sent: Friday, December 24, 1999 9:11 AM
Subject: A86: ti82/85 emulation like rascall


>
> how does rascall emulate
> the ti85 and ti82?  can someone
> who worked on that shell
> or others that emulate give me
> an idea.  thanks.
>
> jimi malcolm
> malcolmj1@juno.com
> http://guide.iwarp.com
>
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