Re: TI Web page update: TI-92 PLUS (US)


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Re: TI Web page update: TI-92 PLUS (US)



There is nothing to indicate the  "archive" memory area is Flash memory.

I'm going to speculate now, but I'm pretty sure that this is the deal with
the "archive" memory:

As the CPU is currently designed, it can only access 256KB of RAM.  That is
because it uses 8 bit addresses for RAM locations.  2^8 = 256.  The other
384KB of RAM is not directly accessible by the CPU for execution of
instructions.  This problem is analogous to the problems with PC's using
more than 1MB of RAM.  Initially the machines only allowed 640K of user
memory, and around 384K was used by the system.  All together there was 1MB
(1024KB) of RAM addressable by the CPU.  This is because the CPU uses 10 bit
addresses and 2^10 = 1024.  It wasn't until the 386 that they figured out a
way to trick the CPU into seeing more memory by using utility files like
EMM386.EXE.  Maybe someone will do the same for the TI92?????

The HP48 calculators also end up with memory for "archive" when you install
memory cards.  This archival memory also cannot be used in the same way that
main memory is used.  The HP48's limit on main memory is 256K, just like the
TI92.  You can add a memory card to expand your ram above this, but it will
be "archival" (although some libraries can be run from this type of memory).

I see no reason to think that this memory will be "flash" technology, which
has some advantages, but in the old days it used to wear out, and maybe the
technology is still in the same position today.

Scott Guth


-----Original Message-----
From: Niklas Brunlid <e96nbr@EFD.LTH.SE>
To: CALC-TI@LISTS.PPP.TI.COM <CALC-TI@LISTS.PPP.TI.COM>
Date: Sunday, November 09, 1997 5:04 AM
Subject: Re: TI Web page update: IT-92 PLUS (US)


>On Sat, 8 Nov 1997 09:14:09 -0500, Richard Cowman
><richard@BOWMANSOFT.COM> wrote:
>
>>The user data archive is Flash memory, not RAM... It gives you 384K of
Flash
>>to store stuff in. Note, however, Flash memory loses storage areas as it
is
>>used. After 1,000+ writes, Flash might lose a few bytes of space hear and
>>there as data cells become unusable. You can read unlimited times from
>>Flash, though. That is why they call it an archive. You should just have
>>some programs you always need in there, not things that change a lot
because
>>it will where out the Flash. Also, the good thing about this 384K of Flash
>>is that even when your calc locks up and clears your RAM, all your stuff
in
>>Flash will still be there!!
>
>It doesn't have to be "real" flash memory since we have a
>battery-backup... maybe it's just not cleared during the
>initialization phase (i.e. when you reset the calc).
>
>>
>>I also have a question. Does anyone know if the 92Plus runs Fargo?? The
FAQ
>>on TI's site says the Plus module directly supports assembly language...
>>does that mean everything will have to re-assembled to work with it?? It
>>mentions ASM at: http://www.ti.com/calc/docs/faq/92pfaq004.htm
>
>Probably. And, with the big ROM in the TI-92 an on-calc text based
>assembler wouldn't be at all hard to do - sources and such could be
>placed in the "flash" mem!
>
>
>Niklas Brunlid - http://www.efd.lth.se/~e96nbr
>PQF Quote follows:
>
>- "What shall I do?"
>- "Well, if you see anything crawl out of the sea and try to breathe,
>   you could try telling it not to bother."
>        -- Rincewind and Eric at the Beginning of Time
>           (Terry Pratchett, Eric)
>


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