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tiosmod - a computer-based unlocking and optimizing program aimed at official TI-68k
calculators OS
Copyright (C) 2010, 2020 Lionel Debroux - TICT (lionel underscore debroux yahoo fr)
Copyright (C) 2020 RANDY Compton
Portions Copyright (C) 2000-2010 Olivier Armand
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Author's motivations
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By chronological order of appearance: optimizing, unlocking, and fixing.
* the initial motivation of this work was scratching a very old itch of mine (before the
creation of FreeFlash): modding TI's OS to optimize several hunks of code that have
bothered me for more than six years.
* the motivation to remove TI's silly protections, while at it, came later, as a
consequence of TI's increasingly frequent and increasingly vicious attacks on our freedom
to tinker with the devices we own...
* the motivation to fix bugs was not present either when I first thought of fiddling with
the OS, but it's a logical consequence of TI abandoning the TI-68k line years ago:
* the la(te)st OS upgrade for 89T and V200, AMS v3.10, was released in July 2005;
* the la(te)st OS upgrade for 89 and 92+, AMS v2.09, was released in March 2003
(and AMS 2.08 & 2.09 for 89 use the 0x340000-0x34FFFF sector, depriving users from
10% of the archive memory they could use on earlier 2.xx versions...).
It's high time we programmers/users tackled the tasks that the manufacturer is no longer
doing !
And now that we have factored, in the summer of 2009, all interesting public RSA signing
keys used in TI-68k and TI-Z80 calculators, we don't even have to use FSign + FreeFlash,
or the older TIB-Receiver, any longer :-)
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Usage information
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* Users just interested in using patched AMS versions should use the provided binary
diffs. Currently, four formats are provided: xdelta 1.x, xdelta 3.x, bsdiff 4.x, ips.
For all of those formats, there's at least one no-fee program that can handle them,
and some of these programs are open source. For more information, see the usage help
printed by each program.
NOTE: the binary diffs provided along with the official distribution perform _all_
changes that the patchset knows how to perform, including:
* hard-coding the standard font (it will hardly make a difference to anyone,
since the possibility of redefining fonts is virtually unused);
* hard-coding the English language (it will make a difference to more users,
since it interferes with language localizations).
* Programmers interested in tinkering with the patcher / patchsets, who know wha
they're doing, can figure out how to compile the program by themselves ;-)
See http://www.ticalc.org/archives/news/articles/14/145/145273.html for links to
RabbitSign and FSign+FreeFlash, the former being preferred nowadays because it's more
convenient.
Standard warranty disclaimer: you're on your own if you mess up calculators by using
pristine or modified versions of the patcher & patchset(s).
Please also note that *redistributing* ready-made, modified versions of TI's copyrighted
OS is illegal in most countries ;-)
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Changelog
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v0.2.7:
* supported AMS versions: no change.
* new fixing capabilities:
* revert AMS 3.10 to the 0^0=1 behaviour of older versions. Patch and 89T test by
RANDY Compton, (emulated) V200 test by myself.
v0.2.6: posted on Cemetech, Omnimaga, TI-Bank and yAronet on 20101024.
* supported AMS versions: no change.
* bugfixes: add an fseek to SearchBackwards* building blocks of tiosmod.c;
* new fixing capabilities:
* fix the bug that can occur when changing batteries (HW3Patch does it).
* improvements:
* the program can now be compiled under Windows as well: msvcrt offers fileno
+ truncate, only called differently. Add explicit Seek() or internal fseek()
before using Write* or Search* - it doesn't seem to be necessary on *nix, but
seems to be on Wine (at least).
Uploaded to ticalc.org on 20101017.
v0.2.5: posted on Cemetech, Omnimaga and TI-Bank on 20101017.
* supported AMS versions: 2.05, 2.08, 2.09, 3.01, 3.10 for all models.
* improvements:
* the Flash memory execution protection is now, hopefully, disabled on HW1
calculators as well. Spotted by Kevin Kofler.
* new enhancement capabilities:
* add back OSVRegisterTimer/OSVFreeTimer + handling code in the AUTO_INT_5
handler and in the timer initialization code, removed by TI in AMS 2.04.
Ultimately, what makes this easy enough is the fact that while the _code_ was
removed by TI, the storage area (2*12 bytes) in RAM was not: it remains
reserved and accessible through trap #9.
v0.2.4: posted on Cemetech, Omnimaga and TI-Bank on 20100925.
* supported AMS versions: 2.05, 2.08, 2.09, 3.01, 3.10 for all models.
* moved more AMS-specific functions from tiosmod.c to amspatch.c.
* improvements:
* checking the OS upgrade's size is now done through an exact match where
possible;
* after finding copies in TI-Connect 1.2, AMS 2.08 for 92+ and V200 have now been
tested on emulator and are officially supported;
* new fixing capabilities:
* fix OSContrastUp/OSContrastDn not to destroy d3 and d4
(bug #53 of http://www.technicalc.org/buglist/bugs.pdf).
v0.2.3b: posted on Cemetech, Omnimaga and TI-Bank on 20100922.
* supported AMS versions: no change.
* new fixing/enhancement capabilities:
* replace buggy AMS trap #3 (wired to OSenqueue, which doesn't work for two
reasons) by UniOS/PreOS-style HeapDeref. Suggested by "Folco" Martial Demolins.
v0.2.3a: posted on Cemetech, Omnimaga and TI-Bank on 20100916.
* supported AMS versions: no change.
* bugfix: typo in the shrinking code for AMS 2.09 for 89 caused incorrect patching,
yielding crash-producing memory corruption, when tracing functions or plots in
the graph screen.
* improvements:
* reject AMS 2.08 for 92+ and V200 until they have _actually_ been tested
(although the current patching code is expected to work, since the AMS 2.08
and AMS 2.09 binaries are very close to each other).
* add and print a patch description below the program's name & version.
Github repository http://github.com/debrouxl/tiosmod created on 20100915.
v0.2.3: posted on Cemetech, Omnimaga and TI-Bank on 20100914.
* supported AMS versions: 2.05, 2.09, 3.01, 3.10 (all models), 2.08 (89 only for now,
I don't have copies of 2.08 for 92+ and for V200 - but the patching code may work
on those as well, seeing that 2.08 and 2.09 are very close to each other).
* new shrinking capabilities:
* EXPERIMENTAL: shrink AMS 2.09 for 89, so as to make it fit in the same number
of sectors as AMS 2.01-2.05 :-)
(USE AT YOUR OWN RISK - only lightly tested !)
v0.2.2: posted on Cemetech, Omnimaga and TI-Bank on 20100914.
* supported AMS versions: 2.05, 2.09, 3.01, 3.10 (all models), 2.08 (89 only for now,
I don't have copies of 2.08 for 92+ and for V200 - but the patching code may work
on those as well, seeing that 2.08 and 2.09 are very close to each other).
* split the program into the building blocks for making a patch (tiosmod.c, under
GPLv2) and the patch itself (amspatch.c, under WTFPLv2).
* new capabilities: shrinking:
* EXPERIMENTAL: shrink AMS 2.08 for 89, so as to make it fit in the same number
of sectors as AMS 2.01-2.05 :-)
(USE AT YOUR OWN RISK - though AFAICT, my testing 89 runs the modified version
just fine)
* now distributing binary diffs suitable for xdelta 1.x, xdelta 3.x and bsdiff.
v0.2.1: posted on Cemetech, Omnimaga and TI-Bank on 20100822.
* supported AMS versions: 2.05, 2.09, 3.01, 3.10 (all models).
* new unlocking capabilities:
* remove artificial limitation of the size of ASM programs on AMS 2.xx;
* remove "Invalid Program Reference" error, artificial limitation of AMS 2.xx and
later when using ASM programs in expressions.
v0.2: posted on Cemetech, Omnimaga and TI-Bank on 20100813.
* supported AMS versions: 2.05, 2.09, 3.01, 3.10 (all models).
* now named "tiosfix", todo/wish list expanded.
* tiosfix now checks and updates the AMS ("basecode") checksum.
* new optimization capabilities:
* OPTIONALLY hard-code English language in XR_stringPtr. After this, language
localizations don't quite work properly...
They have always been a half-baked thing anyway (many TI-BASIC programs work for
English only, it's insanely hard to use a number of TI-BASIC functions in such
a way that the program is portable across all locales), and they make
XR_stringPtr (used, besides the GUI, in the parsing) more than an order of
magnitude slower.
v0.1: first public release, posted on #ti on 20100717.
* supported AMS versions: 2.05, 2.09, 3.01, 3.10 (all models).
* new unlocking capabilities:
* skip FlashApp signature validation (Flashappy);
v0.0: sent privately to several persons.
* supported AMS versions: 2.05, 2.09 (89 / 92+).
* unlocking capabilities:
* RAM execution protection (HW2/3Patch);
* Flash execution protection (latest XPand, extended to all models).
* remove artificial limitation of the amount of archive memory (MaxMem & XPand);
* optimization capabilities:
* rewrite HeapDeref to match the AMS 1.xx code (the many inline versions are
untouched, obviously);
* hard-code the standard fonts in DrawStr/DrawChar/DrawClipChar and sf_width:
the ability to redefine fonts is seldom used, but it slows down (asymptotically)
by ~20% on F_6x8 and F_8x10, by ~80% on F_4x6 (stupidly implemented).
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Todo / wish list
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/ * (BrandonW) make the program into a generic (TI-Z80, TI-68k) patcher with some
scripting language well suited to our needs. Several options:
* (hardest) define some form of a scripting language and turn the program into a
script interpreter;
* use C as a scripting language, interpret it using e.g. TCC (warning, it seems
to be somewhat dead) or the more powerful but heavier LLVM infrastructure ?
* (easiest) don't go much beyond splitting the building blocks and the patch
itself, and compile these files together. This was implemented in v0.2.2,
before, perhaps, doing better some day :)
NOTE1: due to pagination, TI-Z80 OS support is harder than TI-68k OS support...
NOTE2: libti* contain GPL'ed code for loading TI-Z80 OS (stored in Intel Hex
format).
/ * shrink AMS binaries, so as to leave more Flashapp & archive room available to
users and programmers. Significant chunks of data at the end of the OS can be
moved to the space wasted by TI (but rightfully used by PedroM) between
ROM_base + 0x13000 (approximately) and ROM_base + 0x17FFF.
* the only easily reachable targets for shrinking, AMS 2.08 and 2.09 for 89,
have now been shrunk by 316 and 848 bytes respectively (v0.2.2 for 2.08,
v0.2.3 for 2.09). This is enough to make them fit in the same number of
sectors as older AMS 2.xx versions, and give back to the user 64 KB of archive
memory robbed by these upgrades.
* all other versions must be shrunk by at least 16K - this is MUCH harder !
NOTE: could the duplicated "y1-99" "y1-99'" strings be optimized ?
/ * fix TI's bugs for them. AMS has nothing of the magnitude of the bug that pleagues
84+ OS 2.53MP, but it has bugs nevertheless. See the list at
http://www.technicalc.org/buglist/bugs.pdf : fixing bugs 13, 54, 65, 66 and 89
may be reasonably easy. Fixing 25 and 50 (between others) would be nice, but is
presumably harder than the aforementioned bugs.
0 * optimize more functions, such as (but not limited to):
* graphical functions: the whole set is ripe for optimization...
* some fairly low-hanging fruit in the CAS core: for his graphical expression
editor Hail (and byproducts int2str and fastlist), Samuel Stearley re-coded
several routines of the CAS core, e.g. next_expression_index, in a much
faster way...
0 * customization of AMS behaviour, e.g.:
* AMS Extender / EasyChar / ticonst;
* AutoAlphaLock Off.
/ * (??) put new features into the OS, or just restore features removed by TI ??
* PreOS (hard)
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License: building blocks: GPL version 2 only
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This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, version 2 (and only version 2) of the
License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, 5th Floor, Boston, MA 02110-1301, USA
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License: OS patching proper: WTFPL version 2
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This program is free software. It comes without any warranty, to
the extent permitted by applicable law. You can redistribute it
and/or modify it under the terms of the Do What The Fuck You Want
To Public License, Version 2, as published by Sam Hocevar. See
http://sam.zoy.org/wtfpl/COPYING for more details.
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Contact
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lionel underscore debroux yahoo fr