https://github.com/timendus/vera
A hobbyist Texas Instruments graphing calculator OS from the zeros
https://github.com/timendus/vera
os ti-83 ti-83-plus ti84 ti84plus vera z80
Last synced: 8 months ago
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A hobbyist Texas Instruments graphing calculator OS from the zeros
- Host: GitHub
- URL: https://github.com/timendus/vera
- Owner: Timendus
- Created: 2020-01-16T17:48:19.000Z (over 6 years ago)
- Default Branch: master
- Last Pushed: 2020-01-16T23:35:45.000Z (over 6 years ago)
- Last Synced: 2025-01-29T12:47:52.824Z (over 1 year ago)
- Topics: os, ti-83, ti-83-plus, ti84, ti84plus, vera, z80
- Language: Assembly
- Homepage:
- Size: 1.01 MB
- Stars: 2
- Watchers: 3
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# Vera - the Calc Lover's OS
This repository is an attempt to collect the brave repeated undertakings of
several people from the TI graphing calculator scene to build their own
operating system for the calculator from scratch. This project became known as
"Vera". To my knowledge, three separate but loosely related attempts have been
made that resulted in actual code.
My role in the first two attempts was limited (I remember I came up with the
name Vera, which is nice). The third attempt was my own pet project.
## Contributing
If you have more files or links or know more about this than I do, please send
your pull requests my way 😄
## Generation 1 _(early 2006)_
There are two releases of this version, 0.0.1 (5 February 2006) and 0.0.2 (28
april 2006), as part of the "Pre Alpha" release. It actually still has a working
website on sourceforge: http://vera.sourceforge.net/.
The central figure in this effort was probably Brazucs from the UnitedTI
forums. Also, it references `Jim's stuff :)` in the comments [at some point](Generation%201/Vera.0.0.2/p1.asm#L297).
That's undoubtedly "Jim e" from the forums.
The code is pretty small and has a singular purpose, but I think the real
achievement lies in being able to generate a ROM file from scratch that boots
on a calculator and then does anything without being able to depend on the
original OS's subroutines, like outputting some text and getting some input.
## Generation 2 _(late 2006, early 2007)_
Again, I've forgotten who put this together. But we have some actual
[documentation](Generation%202/Documentation) this time, which mentions a couple
of people by name:
```
this file contains the names of the people who wrote code for Vera or whose code was stolen for Vera:
-Jim e ...
-Timendus ...
-flopus maximus, Benjamin Moody
-Jacobbus, Jacob van Ginkel
-and of course all the other people form UnitedTI
maybe I forget some add them please
sources where we ripped most of the code from:
-the API
-Pong OS
-wiki ti
-and more
```
I see my nickname there, although I can't seem to remember actively contributing
code to this project. So that's probably just because they ripped "the API",
which was a project of mine that I added lots of routines to (it was an online
routines repository, the contemporary equivalent of which would be something
like npm).
The [ROM file](Generation%202/Source/Vera%2083%2B.rom) doesn't seem to do very
much or to be very stable, unfortunately. But still, it manages to boot the
calculator and respond to keypresses, which is already quite impressive.
These's also lots of [code](Generation%202/Source). Clearly the author(s) tried
to provide a more generic API as an abstraction of the hardware for programmers.
## Generation 3 _(late 2007)_
This project was announced and discussed here:
http://maxcoderz.org/forum/viewtopic.php?f=3&t=2524 (which unfortunately gives a
403 forbidden as of 2025)
This is the version of Vera I started. The original plan was to write it in C
using [sdcc](http://sdcc.sourceforge.net/), but a lack of experience with that
(or rather: the abundance of experience in writing 'pure' z80) in the community
made quick work of those plans.
Being in university and studying computer science, I started this project with
documentation and testing in mind. So a tool was written (taking ideas from
JavaDoc) to generate HTML documentation from comments in the assembly source
files. The tool (although pretty crappy) has survived and [can be found
here](Generation%203/asmdoc%20tool). Also, we have two versions of the generated
documentation website, that can be seen in the [docs
directory](Generation%203/docs). The latest version can also be [browsed through
online](http://vps.timendus.com/vera/asmdoc/). Several interactive "tests" had
been implemented in the ROM file, but there was also a pretty serious effort
under way of writing a suite of automated tests. How very rigorous of young me
😄
We have a working [ROM file](Generation%203/dist/Vera.rom) for this generation.
The above screenshot shows off all of its features 🥳
The actual Vera source was a different story though. The code was hosted in an
SVN repository that was on my private server. The server was long gone, and it
took me a very long time to recover the source. In 2020 when I created this
repository on Github, the only file I could find was [one that I
copy-pasted](Generation%203/repository/src/devices/memory.asm) on the Maxcoderz
forum, and was able to retrieve there. In 2022 I recovered a bunch of files from
a broken old external harddrive, but most of the directory structure was gone
and I assumed I would not find anything but loose and broken files here, so I
kept on looking in other places every once in a while. It took me until 2025
before I returned to the recovered disk and was able to locate at least some
version of the [original repository](Generation%203/repository) that, to my
surprise, seemed fully intact.
I'm not sure how recent this version is, but it does seem to have the routines
mentioned in the documentation sites and its [tests
menu](Generation%203/repository/src/tests.asm) shows more information than the
ROM that we already had. So I feel confident that this is a very recent version.
There also used to be a wiki with all kinds of info on it. I think I have found
a MySQL database dump that should contain that information, but it also contains
a lot of other information so I'm not publishing that. I may one day try to
generate a version of what the wiki looked like from it. What is still readily
available is the [Google group or mailing
list](https://groups.google.com/forum/?hl=en#!forum/calc-lovers) with lots of
interesting bits of information.
If only we would have had Github back in those days 🙈.