A85: TI-85 ROM/Emulator Issues

To: <assembly-85@lists.ticalc.org>
Subject: A85: TI-85 ROM/Emulator Issues
From: Dennis Munsie <munsie@earthlink.net>
Date: Wed, 4 Mar 98 12:12:15 -0600
Reply-To: assembly-85@lists.ticalc.org


Hello,

     I have a question regarding the TI-85's ROM.  I have a v9 ROM and a 
v10 ROM.  The v9 ROM image I've had for quite some time, and I know that 
it works good.  I just obtained the v10 ROM (no questions please).  Well, 
I tried to use the v10 ROM with the TI-85 Emulator that I have, and 
everything seems to work, but when I do a self-test (MODE, ALPHA, S, 
ENTER), the calculator displays a 0 in the center of the screen, and 
after a second or two, it displays "ROM FAILED".  The v9 ROM counts up 
from 0 and seems to work just fine.

     My questions I have are as follows:

     1) In the v10 ROM, each of the 16k banks ends in FF00, while the v9 
ROM ends in FFFF, just like every other TI-ROM I've seen.  Was this 
changed by TI, or is it a bad dump?

     2) Did TI possibly change the self-test code to write to ROM causing 
the test to fail?  (If this is true, it's a simple, ineffective way to 
protect their ROM images from being used with emulators.  I would hope TI 
would come up with something better than that.)

     3) And what exactly did TI change between v9 and v10?

Thanks in advance for the help

Dennis


Dennis

Maintainer of the TI-8x Emulation Project:
http://members.aol.com/smiley0242

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Re: A85: TI-85 ROM/Emulator Issues

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