13 ms·

The Insane Innovation of TI Calculator Hobbyists

362 points by bkudria 5y ago

RobKohr 5y ago
I used a TI for my physics classes, and wrote code to solve pretty much every problem type. Really, if it weren't for writing the code, I wouldn't have known the subject matter all that well, and would have likely done poorly. By programming it, I understood it deeply. Also, I was able to plow through the exams faster than anyone else. I even made the code show the steps so I could show my work as required.
amznbyebyebye 5y ago
Omg this brought back some ticalc.org nostalgia. I had to check and the site is still going… crazy!
ddingus 5y ago
I missed out on this whole thing being born a bit early. For us, it was 8 bit computers. And for me personally, I grabbed one of the Tandy Pocket Computers and used the crap out of it well into the TI era. Looks like a whole lot of fun! Suppose I could have jumped in, but by then I was away from needing the calculator, ah well.
- thrtythreeforty 5y ago
  I regret that I have less use for calculators than I used to. You can pry my TI-89 from my cold dead hands. Still very useful especially for things like unit math.
  - milleramp 5y ago
    Just gave my son my ti-89 for middle school, apparently it’s a big novelty and has gotten him slightly more motivated for math class. Teacher told him to put his name on it and not let it out of sight.
  - Igelau 5y ago
    The TI-89 blew my mind when I accidentally discovered Exact Mode. I had fed it a problem from my Number Theory homework just for fun... it wasn't supposed to actually answer it!
    - thelittlenag 5y ago
      This takes me back. In high school I actually modded my TI-89 (circa 2001) with a lower Ohm resistor. The clock ran on a simple RC circuit, so you could "overclock" it by soldering in a new resister. Got a pretty impressive bump as I recall. And then when it became common enough games started to support a turbo mode!
  - SAI_Peregrinus 5y ago
    I've still got mine. Though I use an emulator on my phone more often these days. The CAS is still excellent.
- Cixelyn 5y ago
  Yeah, this is a pretty narrow window of the millennial generation. If you had been born too late (e.g. Gen-Z), you'd have high production AAA-production mobile games to play between classes and after school instead. One thing the author overlooks is how game programmers were able to exploit the primitive networking capabilities of the calculator. I fondly remember playing multiplayer Bomberman by plugging two TI-83 together via the 2.5" link cable. I recently had enough nostalgia to pick up a new 2021 TI-84 Plus CE PYTHON unit. On one hand, it hurts to buy a 20+ year old CPU for over $100. On the other, there's something satisfying about still being able to program TI-Basic via muscle-memory using the token-based input.
  - thrtythreeforty 5y ago
    Author here. Great point - I totally forgot to write up CalcNet! It was a protocol designed by KermMartian (DoorsCS guy) for connecting up to 8 calculators to a "local network" of tied-together link ports. There was also bridge software to GlobalCalcNet, which let you sort of VPN your calculator into virtual CalcNet networks over USB.
  - ddingus 5y ago
    I get that. Your comments resonate with me. As for the CPU... I paid a few hundred bucks as I put together a great 8 bit workstation and had similar thoughts. We are buying the system. A lot went into these things. A lot can still come out. And the skills can matter to us. Maybe that helps some.
- peterburkimsher 5y ago
  You're not too old! Embedded systems and home computers grew up together. The TI-84+ that my parents bought me in 2005 was great, especially because my parents paid for it. I feel like any device that becomes popular in schools and is repairable/hackable, will become the platform of the future. The article says "you either knew, or were, that kid" and if you think you were that kid, you probably were. When trying to figure out when embedded systems became mainstream, I accidentally just wrote an incomplete history of embedded pocket computing. 1967: LOGO programming language developed by Seymour Papert. 1970: Sharp QT-8B calculator was the first battery-powered calculator 1972: HP-35 calculator was first scientific calculator 1974: Sinclair Scientific 1974 was affordable, programmable, moddable, repairable. 400 functions in library. 1976: PIC microcontrollers released. 1976: Zilog Z80 launched. 1977: Tandy TRS-80 released, using Zilog Z80 chip. 1977: Apple II released, with colour graphics. 1980: Epson HX-20 released, a laptop with receipt printer and screen. (my dad wrote his Ph.D. thesis on one) 1981: BBC Micro released, targeted at education. 1982: Commodore 64 released. 1984: Apple Macintosh released. 1984: Psion Organiser, 1984 added database, calculator, clock, diary, alarm clock, a-z keyboard. Programmable in OPL, became Symbian. 1985: LEGO/Logo (later Mindstorms) began, with hardware turtles drawing lines using a pen. 1989: Nintendo Game Boy released. 1989: Macintosh Portable released. First laptop with a GUI and mouse (trackball). 1990: ARM founded, as a joint venture of Apple, Acorn (BBC Micro) and VLSI. 1993: Apple Newton 1993 used handwriting recognition, custom ASIC, name PDA. Popular in medical field. 1996: Palm Pilot 1000 in 1996 brought dimensions down to 120x80x18 mm. 1996: TI-83 calculator got added to high school curriculum. 1999: Apple iBook released, targeting education. 2000: Garmin eTrex handheld GPS device introduced. 2000: Nokia 3310 mobile phone released, 126 million units sold. 2001: iPod brought 5 GB disk space, rapidly doubling. Rockbox custom firmware released for Archos in 2002, iPodLinux in 2003. 2004: TI-84 calculator introduced, with USB OTG. 2004: OpenWRT firmware for routers. 2005: Arduino project began. 2007: iPhone decreased disk space compared to iPod but gained capacitive multi-touch screen. 2012: Raspberry Pi released, targeted at education. 2014: ESP8266 released. 2016: iPhone 7 finally exceeded storage of iPod Classic, but removed headphone jack, increased physical dimensions. Embedded hacking involves hardware and software, which makes it hard to specialise. I took LEGO/Logo after school in 2000-2001, then extra ICT classes for IGCSE 2004-2005, then Computer Science for IB 2005-2007, and Electronic Systems Engineering in university 2007-2011. There's plenty more devices and emulators to explore! https://en.wikipedia.org/wiki/Custom_firmware#Other_devices https://en.wikipedia.org/wiki/Custom_firmware#Other_devices
csense 5y ago
The TI Files, where everybody knows your name.
FunnyLookinHat 5y ago
So many fond memories hardware hacking my TI-85. I remember learning to solder so I could add an extra battery pack with 4 D batteries (played too many games!) and writing apps to play music out of the jack. Hacking on my TI-85 and wanting to build websites for gaming guilds (Diablo, Starcraft) is what drove me into computers and software development. There was certainly something unique about that era!
- ivansavz 5y ago
  I learned to solder for TI-purposes too! Not for battery but to build the 2.5mm-jack-to-serial connector cable (I was too cheap to buy an official one, but successfully wired together the 2-3 resistors and diodes necessary to make the cable work. It was not pretty, but it worked!)
  - cyberge99 5y ago
    Same here! I’m going to see if I can find the cable around here somewhere.
  - FunnyLookinHat 5y ago
    Oh that's awesome! I still have my TI-89 - maybe I should find some weekend time to do some projects on it... that sounds like a fun one!
  - charles_f 5y ago
    Same here! I initially had the cable fit with scotch tape and then later soldered to make it work properly. Also first trip to an electronics store, was terrifying to enter a specialist shop with close to no knowledge
gamegoblin 5y ago
Like many here, I can attribute where I am in life today largely to TI calculator programming. I made many friends on Cemetech with whom I still keep in touch, including a few named in this article. I racked up thousands of posts on the Cemetech and United TI forums and spent countless hours hanging out in the game Blockland which was also popular among those folks in the mid 2000s. To me, one of the most impressive folks in this list is calc84maniac, who joined the scene a year or two after me, but quickly surpassed me in skill, becoming a z80 ASM whiz at the age of ~13 or so, whereas some of the other (very talented) folks were at least STEM university students. I know a few people in this article such as SirCmpwn are on HN, too, so hopefully they chime in this thread. Some of the most memorable things about programming in BASIC on these calculators were the absurd constraints. Your whole program was limited to a few kilobytes. You only had 27 floating point variables, a few lists of floats with a maximum length of 999, no real functions or stack or anything, etc. You’d shave bytes by taking advantage of syntactical quirks that the interpreter happened to accept, like not closing parentheses at the end of a line. I don’t have much of value to add other than expressing some serious nostalgia.
- NaturalPhallacy 5y ago
  >Your whole program was limited to a few kilobytes. You only had 27 floating point variables, a few lists of floats with a maximum length of 999, no real functions or stack or anything, etc. You’d shave bytes by taking advantage of syntactical quirks that the interpreter happened to accept, like not closing parentheses at the end of a line. I found that smaller programs just ran faster. So I took one I'd written to convert from ASCII strings to binary strings and back. Yes, there's a built in function to do this, but it's very limited. Mine used string representations and so the only limits were memory...Then I changed all the variables to single letters to save space...and rendering the code completely indecipherable in the process. Learning the hard way that "human readable code" is very important at a very young age.
  - gamegoblin 5y ago
    One reason for this was that GOTO was a main control structure in TI-BASIC (since it lacked user-definable functions), and AFAIK on hitting a GOTO, the interpreter scanned the program from top to bottom to find the corresponding Label. So it was very easy to write loops than ran in O(program size). This was strong motivation to learn how to use While and For loops.
makeitdouble 5y ago
To stay true to the endless rivalry, here is the HP calculator resources: https://www.hpcalc.org https://www.hpcalc.org Both the TI and HP were tremendously good entry points into programming and, especially for kids who had little interest in or no access to computers.
- agumonkey 5y ago
  HP RPL is one serious gem. HP48 series had lambda arrow syntax in 1990. << a -> << a a + >> >> All in your jeans pocket.
  - peterfield 5y ago
    I was wondering when I'd find this comment :) I was in high school early in the early 90s. I programmed a 2-dice game drinking game on a HP48.
- optimalsolver 5y ago
  I bet most fans of stack-based languages got their starts on HP calcs.
jurassic 5y ago
TI-83+ played a huge role in my formative years as a programmer/nerd. This was early 2000s. If you like calculators, I also recommend checking out the visual history of vintage TI calculators at http://www.datamath.org/ http://www.datamath.org/
- billfruit 5y ago
  Please don't take it the wrong way, but by early 2000s PCs were widespread, so wouldn't it have been easier to get into programing through PCs than through these very restricted calculators? I never understand the American fascination with programmable calculators. To me they sound like a racket by calculator manufacturers and education authorities to mandate an unnecessary and expensive device on to students. In many other countries students get through high school and even many undergraduate courses (like CS for example) without needing any calculator at all. Perhaps this is due to the greater focus on analytical problem solving than numerical solutions which is perhaps done in the US?
  - yareally 5y ago
    There's a few reasons that only make sense if you were in high school at that time in the United States: - Many schools didn't offer programming courses in the 00s (including mine) - Ti calculators came with a large manual and a list of the keywords/functions built into it - Lots of free time while in high school. Study halls, for example - Sharing apps could be done through plugging a serial cable into two calculators - The calculators were ubiquitous for students - Many of us didn't have great internet at the time, so getting programming resources wasn't easy (manuals, compliers, other tooling)
  - jurassic 5y ago
    In the pre-smartphone age, calculators represented the only widely available mobile gaming platform for bored high school kids. That motivated a lot of people I know, including me, to dabble in programming.
  - jude- 5y ago
    As someone who cut his programming teeth on TI calculators, I think the fascination from the student side is because it hits a "sweet spot" for casual and budding professional programmers alike: * It's very easy to get started. The built-in TI-Basic interpreter is fully documented in the manual, and is expressive enough to be useful for a wide variety of imminently useful tasks (e.g. writing programs that help you with your homework) without too much of a time investment. Moreover, your math teacher can likely help you, since they probably also write their own TI-Basic programs. * It's a "small" system. You can comprehend how everything in the hardware works end-to-end if you make it to C/assembler programming (doable without professional or academic training). * At the same time, it's a rich and complex enough system that you can make non-trivial games that you and your friends will share and enjoy playing surreptitiously in class. * Everyone you know has one, which means there's a large online presence and user community to help you get started and who will delight at the programs you write. TI calculators precede the Raspberry Pi, smartphones, and netbooks, so there was at one point a "nerdy coolness" factor of having a pocket-sized programmable device you could take everywhere. They were also more affordable than Palm Pilots, and since everyone had one, it was less nerdy to be seen using one in school. Just my two cents.
NaturalPhallacy 5y ago
I sold my first "app" in 1997 for $1. It was a TI-85 program custom written for my chemistry class. It had a couple of minor useful things, but the biggest thing is it would stuff atomic weights into their canonical symbol names in memory, and clear them when you're done to save memory. For example, 2O (two-oh, two Oxygen atoms) was a valid expression that yielded 32. And no, not all of them are available though it's been 24 years so I don't remember which weren't but it was surprisingly few. I thought it would be a immoral to sell something for more than $1, that when I still had it after selling it. I probably could have charged $50. I think I was 16 or 17. But I beat apple to the "$1 app" game by 11 years. And it's part of what made me go into computer science -> programming. I grew up poor, so we didn't have a computer in the house, and no internet either. So I carried around the calculator and it's manual for years in High School.
userbinator 5y ago
The Z80, as well as its contemporary competitor the 6502, are still in production and found as a core in various cheap SoCs for toys and other simple consumer electronics. It's certainly more than enough processing power for a moderately complex calculator, but compare the responsiveness of a TI calculator to the regular Windows (10) calculator running on a machine with several orders of magnitude more processing power --- and the former wins. I've noticed that programmers who have worked with constrained systems and/or started with low-level languages tend to write better code in general (smaller, faster, often both; and less buggy too) by default than those who haven't; I guess the exposure helps develop an intuition for "how much program/computer ought to be enough" to solve a problem.
jdkee 5y ago
Modern RPN calculators (clones). https://www.swissmicros.com/products https://www.swissmicros.com/products
- jonathanstrange 5y ago
  Unfortunately, only their hardware is modern. :( The software is outdated and too limited. I'm annoyed that HP basically shrunk down their calculator team down to two people or so and that nobody is working on a worthy successor to the HP50g. The HP Prime is definitely not a worthy successor. I especially dislike the incongruent mixture of two different calculator engines, and now they've added Python to their own programming language to make it even more confusing. I guess engineers all use tablets or Wolfram Alpha by now and so they figured there is no market for it.
modeless 5y ago
The magic of the TI calculators is that the hardware is simple in a way no other widely used platform is. Way simpler than something like a Raspberry Pi. No GPU, no BIOS, no PCI, no USB, no kernel. You can directly flip pixels on the screen by just flipping bits in memory at a known address and you can see what keyboard buttons are pressed by reading from another address. And yet despite the utter simplicity, these things are sold and used by the millions even today, so software written for them has a market. I think every CS student should have a chance to program a simple yet real system like that.
- divbzero 5y ago
  I wish someone had explained the mapping of memory to input/output to me in high school. Had I known it was so straightforward I would have ventured beyond programming BASIC on the calculators.
- thrtythreeforty 5y ago
  Agree, the system is uniquely approachable for low level. The simplicity is beginning to be a problem for Texas Instruments who faces competitive pressure from other companies who have a more modular codebase and can just drop in Python support. TI is heavily invested in their z80 assembly codebase and can't get things like CircuitPython to build on ez80, leading to hacks like shipping a totally separate ARM microcontroller to run the Python environment, with the z80 playing dumb terminal. A smarter solution would be to virtualize the z80 portions on basically any other architecture and slowly start moving to C wrappers for TI-OS functionality.
- userbinator 5y ago
  They do have a ROM, but it's basically equivalent to famous 80s home computers like the C64 and ZX. Also early games consoles like the NES (which truly doesn't have any ROM---it's all in the cartridge).
billfruit 5y ago
I never understand the American fascination with programmable calculators. To me they sound like a racket by calculator manufacturers and education authorities to mandate an unnecessary and expensive device on to students. In many other countries students get through high school and even many undergraduate courses (like CS for example) without needing any calculator at all. Perhaps this is due to the greater focus on analytical problem solving than numerical solutions which is perhaps done in the US? (Reposting this as a direct comment, after posting as a reply a comment below.)
- searchableguy 5y ago
  Which country are you from/talking about?
- divbzero 5y ago
  Is the US really the only country where programmable calculators are used heavily in high school math classes?
  - eliasson 5y ago
    No, these calculators were fairly popular in Sweden as well (at least during the late 90s).
  - pjmlp 5y ago
    In Portugal we used them as well, but we don't suffer from a TI monopoly on the education system. Anyone is free to pick whatever they wanted, so we had a mix of Casio, TI and HP calculators. The Casio Basic tablets were the most famous ones, FX-850P. https://en.wikipedia.org/wiki/Casio_FX-850P https://en.wikipedia.org/wiki/Casio_FX-850P I eventually had the follow up model FX-880P, after using FX-4500P during high school. https://www.casio-calculator.com/Museum/Pages/FFF/FX-4500P/Casio%20FX-4500P.html https://www.casio-calculator.com/Museum/Pages/FFF/FX-4500P/C... https://www.casio-calculator.com/Museum/Pages/FFF/FX-880P/Casio%20FX-880P.html https://www.casio-calculator.com/Museum/Pages/FFF/FX-880P/Ca...
- toast0 5y ago
  Sure, they're a racket. But they're also a handy tool. You can plug in a bunch of arithmetic, and it just does it, but you can easily edit and redo. They can graph some functions, and do some of the brute force stuff (like newton's method etc), so you can concentrate on the thinking. If you spend the class time writing a program to solve the homework, instead of doing the homework, you've practiced a life skill and probably understand the material pretty well. If you get the 68k based calculators (ti-92 and ti-89), they've got a symbolic algebra system and can do a lot of cool stuff, although giving that to a high schooler may not be the best choice.
DavidPeiffer 5y ago
Since we're swapping TI calculator stories... In 8th grade Geometry class circa 2007, I had an awesome teacher and loved the subject. I found an extra TI-83+ laying around the house from my brothers. I found a guide online and started building simple programs. A few weeks later, there was a quiz. I asked the teacher if it was permissible to use calculator programs on the quiz. He thought a moment and said it was fine as long as I wrote them myself. So I wrote a very simple program that probably did little more than guide which formula to use in a basic decision tree. It was the hardest quiz of the year, it was just difficult content. My class has 1 A, 1 B, 1 C, and about 23 F's. I was the B. After that, graphing calculators weren't allowed. Mad respect for Mr. Gass. He had two Apple IIe's and had programmed Wheel of Fortune and Jeopard! for review days ahead of tests. He had a couple TV's around the classroom so everyone could see the game well, and would turn on Bill Cosby during some working sessions because at the time, he was a well respected man. Mrs. Gass was also a math teacher. Some students who had both teachers made shirts which advertised "I passed Gass twice"
- nicolas_t 5y ago
  > So I wrote a very simple program that probably did little more than guide which formula to use in a basic decision tree. > It was the hardest quiz of the year, it was just difficult content. My class has 1 A, 1 B, 1 C, and about 23 F's. I was the B. Slightly out of topic but one of the most bone headed decisions I've seen politician do is banning the use of custom software during exams. In France, they created a law forcing all programmable calculators to have an exam mode, during exams (including the national baccalauréat), the calculator needs to be in an exam mode with a special blinking light appearing and during which time students are not allowed to access programs. What I liked when I was a child about the exams in France is that they tended to be difficult without multiple choice questions and needing students to master the material, With such exams, having previously stored the formula in a calculator is of little value and so this anti-cheat mode doesn't help. It's also a more realistic example of real life when we all have access to Google, yet just having the answer doesn't make all of us doctors, mathematicians, engineers or lawyers. On the other hand, creating useful little programs to help verify things has value, it helps with learning, it gives motivations to kids to learn how their calculator work and is a great way for kids who are mostly exposed to lockdown platforms to start programming.
bane 5y ago
The TI calculators have ended up serving American students in a similar way the BBC Micro served British students and now how the Raspberry Pi is serving everybody. "Cheap", ubiquitous, hackable, easy to understand computers. Many of the developers I know can think back to the first computer they ever wrote a program for, but if you press them, they'll often realize that they actually first wrote software for the TI calcs. https://ticalc.org/ https://ticalc.org/ is a treasure of the internet.
- ticalc-isaacs 5y ago
  > https://ticalc.org/ https://ticalc.org/ is a treasure of the internet. Thanks! (I founded ticalc.org back in 1996.) While calculators weren't my first programming experience, starting ticalc.org was formative for me. Getting all the TI hobby site maintainers (and ZShell developers) involved, registering the domain, setting up the server (Slackware!), etc. really led to my career in tech. While I regularly encounter new technical challenges, almost every organizational challenge I've ever encountered as a technical leader since has had precedent from working on ticalc.org. I do wonder whether and how ticalc.org should evolve now. Traffic and activity peaked before smartphones became ubiquitous (for obvious reasons) but it's still pretty popular - See https://ticalc.org/about/webstats.html https://ticalc.org/about/webstats.html. We've always been strictly non-commercial and I don't envision changing that (mainly because I believe in our all-volunteer public service mission, but also because any serious encounter with bureaucracy would probably be fatal for the project.) But I am thinking about succession - what happens when our active staff no longer have the time or energy to maintain it. I wonder if HN'ers with comparable experiences with long-running volunteer projects like this have some wisdom on this topic?
  - bane 5y ago
    I have no particular advice for you, but greatly appreciate the site and all the fun and utility I received from it. At the very least you might want to consider periodic snapshots of the site and all the software be put up on archive.org.
  - thrtythreeforty 5y ago
continuational 5y ago
Fond memories! I wrote this little game in z80 assembler in highschool: TI Slimeball: https://www.ticalc.org/archives/files/fileinfo/290/29096.html https://www.ticalc.org/archives/files/fileinfo/290/29096.htm...
- mikeknoop 5y ago
  That’s cool! I also made a version of this game around the same time: https://www.ticalc.org/archives/files/fileinfo/248/24890.html https://www.ticalc.org/archives/files/fileinfo/248/24890.htm...
- Jyaif 5y ago
  Slimeball! I wrote a TI89 version: https://www.ticalc.org/archives/files/fileinfo/340/34000.html https://www.ticalc.org/archives/files/fileinfo/340/34000.htm...
- NanoWar 5y ago
  I played it back then. Thank you!
dietrichepp 5y ago
There was a puzzle game I had for the TI-86 called simply “dstar”. I always wondered who made it. When I looked it up, it looks like it was based on an HP-48 game by the same name. I’ve ported it to JavaScript, and it runs in the web browser. I also added the ability to show the solution to each level, and skip to any level. https://www.moria.us/games/dstar/play https://www.moria.us/games/dstar/play
- zerocount 5y ago
  Just played it and it's a lot of fun! Thanks for sharing the link.
distantaidenn 5y ago
Ohh, TI stories! Here we go! "Hey, distantaidenn, I wanna talk to you after class." These were the words of my then high school math teacher. I wasn't worried, I was a good student. Little did I know, this would shape my career for the next 20 years. When after class came, my teacher handed me a brand spanking new TI-83. "We're gonna be using these in class from now on. Take this home for the weekend, learn how to use it, and teach the rest of the class." I held in my excitement, and took the device, along with its 1-inch thick manual. I pored over the manual. Before I knew it, I had mathematical functions dancing across the screen. All of our current math equations set up to accept variables and spit out answers. I didn't know it at the time, but I was "programming." I began to dabble in TI-Basic -- I had no idea what it was, but apparently, it was the language this giant calculator used, and I'd have to learn that language to make this machine do my bidding. So I learned it. The next year in school, I signed up for an elective Programming class, and lo and behold, it was in Basic -- I thought to myself, this looks familiar, I know this! I finally made the connection that I had been "programming" the whole time. From then I was hooked. Fast forward to university, I gained a degree that was as far from programming as possible, but I always had my scripts. I was the guy that could talk to computers. I was at home on the command line. And I knew enough html and JS to make a shitty web page, if necessary. And here I am now, still engineering and managing, and making (I'd like to think) not so shitty products for a living.
- BigHatLogan 5y ago
  Great story--thanks for sharing! It's interesting how the unexpected, serendipitous moments can have such downstream effects on our lives! Just out of curiosity: what did you end up studying in university? And how come you didn't study computer science / programming despite acquiring an interest for it earlier in your life?
  - distantaidenn 5y ago
    Thanks! I decided to delve into the "pure" sciences of mathematics and physics. I figured I'd end up in the ivory towers of academia. And of course, like many other undergrads, I ended up major hopping a bit. I never considered programming as a career until it happened.
DamnInteresting 5y ago
So many whipper-snappers here talking about their TI-83+ and later models. When I was in high school ca. 1994 my trusty TI-82 kept me quite busy writing BASIC games. We used to share games with the data sharing cable, I wonder if any of mine still survive somewhere. I still have the physical calculator tucked away in some box, but it is certain that the batteries are long since dead, and all of the volatile memory faded away. In high school, my calculus teacher discovered that I had written programs on my TI-82 to help me solve homework questions. Much to my surprise, he approved! He explained that his objective was to teach us to solve the problems using whatever tools we had at our disposal—writing a BASIC program to solve the problem was not cheating, rather it was making the best of my resources.
- tgv 5y ago
  I honed my skills on a TI 58. What a machine. I wrote a simple 8 queens solver, which took nearly 30 minutes to reach the first solution. Great times.
  - dboreham 5y ago
    Seeing the headline I came here thinking I'd read about TI-58/59 hacking. I actually had no idea there was a whole later generation of TI calculators based on the Z80! I spent endless hours messing around with my Dad's TI-58 in 1977 and recently bought two examples on a popular online auction site to preserve for when I have that kind of spare time again.
- dubbel 5y ago
  Same here! I had to "delete" my programs though (I think I was able to hide/archive it and restore it after the teacher had checked my empty program list... or did I write an emulator of an empty programs list? I can't remember). I also wrote the first TI-BASIC tutorial in German on my first blog as a high-schooler. It got pretty popular with it's target group (other high-schoolers who were bored in Math class), and 12 years later I got an email by an unknown person who had randomly stumbled upon my blog again and thanked me for writing it. That one email had been enough to make it all worth it by itself. Edit: Here it is: https://archive.haukeluebbers.de/ti-basic-tutorial/ https://archive.haukeluebbers.de/ti-basic-tutorial/
mikeknoop 5y ago
Learning to code and hack on TI 83+’s definitely has through lines to my career nearly 20 years later. One thing I’m particularly proud of was figuring out how to build an Assembly program workaround for TI’s “testguard” (a tool to force clear someone else’s calculator memory via link cable) in middle school: https://mikeknoop.com/upload/SafeGuard.zip https://mikeknoop.com/upload/SafeGuard.zip
mbg721 5y ago
Never underestimate a bored person with something that looks to their boss like work.
bo1024 5y ago
I'll also chime in. Early in high school, went from writing one-line basic programs to reading the assembly and C source code of Phoenix and other games. Wrote some games of my own in C and assembler. Now pursuing a career in CS. A very strange entry point in retrospect, but such a serendipitious one.
tablespoon 5y ago
> In the mid-to-late 2000s, you either knew, or were, that kid in grade school. You know. The one who could put games on your graphing calculator. Nit: That was totally a thing in the 90s as well. In junior high, some (actually pretty non-techie) kid knew (I think) a college kid who installed ZShell (http://tistory.wikidot.com/zshell http://tistory.wikidot.com/zshell) and some games on his TI-85. Pretty soon everyone else got them via memory backup. Eventually those got boring, and I was the kid who got the Graph-Link kit to get new game. This article actually seems to be kinda unaware of the earlier phases of this subculture, that were centered on the TI-85/86 and TI-92/89.
lambdaloop 5y ago
Ah I was so into writing TI-BASIC (and eventually, experimenting with z80) on my TI calculator! I would be carrying it to every class. This was before smartphones and I had a lot of times where I had nothing better than to write program on the calculator. I wrote so many things, like a hangman game (with a wide vocabulary) and an RPG fully in TI-BASIC, with a 2D map and a combat system. You could store only a limited number of pictures, so I made up a format for mapping pictures into strings, with a corresponding encoder and decoder. My favorite program I wrote is ELIZA, a copy of the famous therapist AI program (actually inspired by the alt-text of the xkcd linked in the article!). It had like 30 rules or so and worked remarkably well, to the extent that I would talk to it often through my problems.
ecpottinger 5y ago
AAAARRRRHHHH! Reading the link I saw the solution I missed decades ago when I tried to use POV to make my PET create a colour display. Just reading the section on how they did 4 levels of grey scale was an eye opener. Yes, I got some colour by flashing squares on and off but it was unwatchable. I did the flashing for the entire screen together! Just by breaking up which squares flashed at different times I can now see would have made a big difference. Almost 40 years to learn what I did wrong.
sbrother 5y ago
Oh man, getting obsessed with TI-82 BASIC in middle school is definitely the reason I have the career and life I do today. I remember after years of dealing with ~36 variable slots and all the other insane limitations, my parents got me a TI-89 for Christmas and it changed everything. You could perform "indirection" on a constructed string, which opened up all kinds of awesome techniques. And you could draw lines and points on the canvas! I built an incredibly slow pokemon clone and a theorem prover before a kind mentor suggested I try programming on the computer. I hope these sorts of experiences will still be accessible for my kids. Having a school-mandated device with a button labeled "PROGRAM" that took you straight to a BASIC interpreter made it possible for someone like me, growing up in a rural area with zero parental technical knowledge, to end up where I am today.
- hutzlibu 5y ago
  "I hope these sorts of experiences will still be accessible for my kids. " If they surfe the web from their computers, they are just a click away, from a WebIDE, called dev tools, much more powerful, and millions of tutorials how to use them. Thd opportunity they have.
stkdump 5y ago
I used tigcc to write a program that can draw the root locus (https://en.m.wikipedia.org/wiki/Root_locus https://en.m.wikipedia.org/wiki/Root_locus). I had a version that ran in ti basic at first, but it was too slow because it had to solve a polynomial (order 3 or 4) per pixel. It was my way of cheating, because the calculator was allowed in most exams. I considered it not quite cheating, because I figured being able to code the solution should also count. I also coded up ti basic programs that instead of just spewing out the solution to some types of maths problems also gave the steps. That saved a lot of time in maths exams so that I had more time for the problems that required more thought.
johnebgd 5y ago
Finished high school in 2003. Was told to pickup a graphing calculator in 6th or 7th grade. My family bought me a second hand TI82. I might be the only student to have had one malfunction but the = button stopped responding that first year. My family got me a TI83 after that. I would later buy myself a TI83+ when I started working part time. That was my first exposure to basic. I would like to believe I am also still the record holder for an uncle worm high score.
znpy 5y ago
I went back to school and was thrilled to have an excuse to use my ti86 once again :) Love that thing.
m0ngr31 5y ago
I was the same way but with Casio calculators. Got me into programming and the casiocalc.org forum was the first online community I was ever active on. It's like a ghost town now but it was a good time back in the day.
- jpatte 5y ago
  Same here. The "Casio hackers" community was nowhere near as large as the TI folks, but we had some good times and some impressive projects too. :)
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em3rgent0rdr 5y ago
Fond memories myself of writing a texture rotator/zoom demo and squeezing every clock cycle out of it.
wiz21c 5y ago
I found this which has some screen shots : https://www.youtube.com/watch?v=Jo_WgbUfNxc https://www.youtube.com/watch?v=Jo_WgbUfNxc
gambiting 5y ago
Well, I'm jealous of you Americans being allowed graphing calculators. As someone who went to Polish shools in the same period of time, only basic calculators were allowed(addition/multiplication/subtraction/division and nothing else). I've had a graphing calculator but it was just a novelty to play with at home since it wasn't allowed at school.
- inglor_cz 5y ago
  I passed through Czech schools with my second-hand TI-83 calculator. They only probably found out what it can do afterwards. That second-hand TI-83 cost me like half of average salary (in 1994), but it worked really well. I still have it, but I no longer have any use for it.
thewakalix 5y ago
> This is not a coincidence because nothing is ever a coincidence with xkcd. I love these little in-jokes.
- thrtythreeforty 5y ago
  Haha I am glad someone noticed :)
ttoinou 5y ago
I started programming because I was bored in school at 13 yo and using a TI 83 was accepted in almost all classes. I coded a dichotomic number guesser, Collatz path grapher, unbeatable tic tac toe, minesweeper with recursive finding of surrounding blank cells, IFS (iterated function system) grapher generated from random points (to draw fractals), a Connect Four etc. All this with a 6 lines screen and a huge amount of noise around me constantly. When I got home, I would link the TI on my computer and install a copycat of Pokemon Blue/Red for GameBoy that someone coded in assembly and realize how awesome some others people were, and I had still so much to learn
Foobar8568 5y ago
I remember playing "Zelda" clone on my HP48GX back in the late 90s, what an era and impressive feat. And if I am not wrong, a lot of today CAS solvers on calculators are derived from https://www-fourier.ujf-grenoble.fr/~parisse/giac.html https://www-fourier.ujf-grenoble.fr/~parisse/giac.html and from the author of the famous Erable (Mapple in French :o )
lawl 5y ago
The guy that developed the gameboy emulator mentioned in the article is now working on a new version that jit-recompiles gameboy roms: https://github.com/calc84maniac/tiboyce/tree/dev https://github.com/calc84maniac/tiboyce/tree/dev
crocal 5y ago
Dude. TI-81 was my high school calculator. I got pretty famous at some point for managing to squeeze into it a decent RPG with monsters, health points and some story line. Other geeks were jealous and jocks patted me on the back for providing distraction. The challenge was the available BASIC program memory. We spent the next few months figuring out how to reduce the footprint to the bare minimum to add more gameplay. No internet at the time. Just our brains and the manuals. I chuckle at the idea of what we could have done if we had been hinted access to assembly and pixel flicker tricks to have 4 colours. EDIT: Typos
yrcyrc 5y ago
Circa 1995/6 was it for me but on Casio calculators [1] There were books devoted to it, I was able to program games, school cheat notes, brilliant memories. [1] https://fr.wikipedia.org/wiki/Casio_CFX-9960GT https://fr.wikipedia.org/wiki/Casio_CFX-9960GT
shmageggy 5y ago
It appears Durk Kingma, the author of the greyscale library mentioned, is renowned AI researcher http://dpkingma.com/ http://dpkingma.com/. Pretty neat.
stephc_int13 5y ago
My first big project was also done on a similar calculator. A few years before the TI era there was a strong HP-48 scene in France and I believe that many of the early work and games on TI-8x and T-9x were inspired by what was already available on HP-48. Here is my own contribution at the time: https://www.hpcalc.org/hp48/apps/shell/ https://www.hpcalc.org/hp48/apps/shell/ A multitasking alternative OS and a few apps, I learned a lot working on this.
jaco8 5y ago
All this brings up long subdued memory .... my HP-25 ,which had cost me one months work during school holidays.. I still remember when I got payment and the next day walked into the shop and told the perplexed salesperson : I want this! He thought nobody in his right mind would buy a calculator without an equal sign button. Anyway I used it from 1975 to abt 1993 when the battery leaked .
samgranieri 5y ago
The first program I wrote was a quadratic equation solver on my TI82 in the mid 90s. I bought the link cable and enjoyed playing assembly games on my TI86.
trackrn6 5y ago
Before iPads were commonly used while flying. My first program was setting up an app to calculate wind correction and fuel estimates into my TI-83. It was the first time I was able use Trig and programming to solve a real world problem.
- ChicagoBoy11 5y ago
  hahah that's awesome! Makes me wonder now if anyone ever took a checkride and instead of an e6b just whipped out a TI83 in the middle of it. I'd pass that guy instantly! hehehehe
ChicagoBoy11 5y ago
I'll never forget this project a friend and I worked on because of the "clear your devices" procedure they had us do before every test to make sure we weren't cheating or something. At that point we could archive things and whatnot, but it was just a PITA to deal with it and we kept getting annoyed at having to clear our calculators. So then, of course, we made our own program that would simulate the memory cleared screen, and we used it successfully. Of course, we got paranoid lest anyone would find out, so we ended up just adding to it, so you could then interact with the calculator and even do math on it, so it wouldn't seem like you were interacting with our program. Funnily enough neither of us ever came close to using it for cheating -- I mean, we didn't need it. But I maintain that in the couple decades since, it was probably some of my best work.
h0nd 5y ago
My first few basic lines of code were written on a TI83+. Nostalgia.
gorkish 5y ago
Though I have absolutely no proof of it since that era is both a black hole for usenet and before calc-ti.org, I believe I can claim to have published the first fake-grayscale demo in asm for the TI-85. This would have been in maybe 1993 or 1994 I think. It was a 4-frame animation of Bevis and Butthead headbanging, and since it was essentially stored as 16 uncompressed bitmaps, it took the calculator's entire memory. Getting grayscale out of a mono LCD was obviously not a unique idea, but at least I independently arrived at the notion that it could work. I hammered out the TI-BASIC version and proved it sorta worked, but only if I could make my program run fast enough. I should mention that I was 12. Before zShell existed, my only programming as a kid had been things like BASIC and Logo; the closest I ever got to anything more fun was some type-in programs that used a whole lot of opaque POKE and PEEK statements, and I got frustrated trying to get C64 programs I got from a book at school working on the Apple ][. I was shit at porting software in middle school. Going from this straight to z80 asm was insane, but the naivety of youth gave me confidence. My programs would be harder to write but they would run faster. Naturally the fastest program would be the hardest to write, so z80 asm it was. I was hooked. I became a software developer. I remember specifically in those early days emailing with Magnus Hagandar, Dan Eble, and Mattias Lindqvist. Thanks to each of you and to all the other early TI fans who helped me along and put up with me. In later years I learned most of this community were also basically kids playing adult on the early Internet. What a time it was!
jeffalyanak 5y ago
https://www.irrlichtproject.de/houston/ https://www.irrlichtproject.de/houston/ Houstontracker 2 is a surprisingly powerful music software for TI calculators which accomplishes its magic by bit-banging the serial data port to produce stereo audio!
davegauer 5y ago
The first piece of "real" software I ever wrote was called "DISC" because it's initial feature was printing out the discriminant of a parabola. But I added to that program as the high school algebra class continued so that by the end of the class, it could spit out answers to all sorts of problems. Everybody loved it. A fellow student assumed the name stood for "DISCovery", so I retroactively made it so. After that came a little text-based adventure game that made the rounds. And then what was to be my magnum opus: a graphical adventure with locations you could select with a "mouse" cursor controlled by the arrow keys. Everything was first plotted out on graph paper and hand written because it was actually FASTER TO WRITE TI-BASIC ON PAPER than entering the program using the calculator keys. I had overcome the biggest technical hurdles and it was looking great when, for some reason, I decided to change the AA batteries AND the coin cell battery at the same time. Everything else was backed up to friend's calculators. But not that graphical adventure game. It was gone as soon as that coin cell came out. I did not have the heart to re-enter the program and the school year was ending anyway. I still remember that sinking feeling when I realized my work was lost.
matyo91 5y ago
Hi ! This article tell a lot from me. Have a look at all my TI-89 programs I developed at high-school. https://apps.darkwood.fr/ti89 https://apps.darkwood.fr/ti89 Was good time !

362 points by bkudria 5y ago

I used a TI for my physics classes, and wrote code to solve pretty much every problem type. Really, if it weren't for writing the code, I wouldn't have known the subject matter all that well, and would have likely done poorly. By programming it, I understood it deeply. Also, I was able to plow through the exams faster than anyone else. I even made the code show the steps so I could show my work as required.

amznbyebyebye 5y ago

Omg this brought back some ticalc.org nostalgia. I had to check and the site is still going… crazy!

ddingus 5y ago

I missed out on this whole thing being born a bit early. For us, it was 8 bit computers. And for me personally, I grabbed one of the Tandy Pocket Computers and used the crap out of it well into the TI era. Looks like a whole lot of fun! Suppose I could have jumped in, but by then I was away from needing the calculator, ah well.

thrtythreeforty 5y ago
I regret that I have less use for calculators than I used to. You can pry my TI-89 from my cold dead hands. Still very useful especially for things like unit math.
- milleramp 5y ago
  Just gave my son my ti-89 for middle school, apparently it’s a big novelty and has gotten him slightly more motivated for math class. Teacher told him to put his name on it and not let it out of sight.
- Igelau 5y ago
  The TI-89 blew my mind when I accidentally discovered Exact Mode. I had fed it a problem from my Number Theory homework just for fun... it wasn't supposed to actually answer it!
  - thelittlenag 5y ago
    This takes me back. In high school I actually modded my TI-89 (circa 2001) with a lower Ohm resistor. The clock ran on a simple RC circuit, so you could "overclock" it by soldering in a new resister. Got a pretty impressive bump as I recall. And then when it became common enough games started to support a turbo mode!
- SAI_Peregrinus 5y ago
  I've still got mine. Though I use an emulator on my phone more often these days. The CAS is still excellent.
Cixelyn 5y ago
Yeah, this is a pretty narrow window of the millennial generation. If you had been born too late (e.g. Gen-Z), you'd have high production AAA-production mobile games to play between classes and after school instead. One thing the author overlooks is how game programmers were able to exploit the primitive networking capabilities of the calculator. I fondly remember playing multiplayer Bomberman by plugging two TI-83 together via the 2.5" link cable. I recently had enough nostalgia to pick up a new 2021 TI-84 Plus CE PYTHON unit. On one hand, it hurts to buy a 20+ year old CPU for over $100. On the other, there's something satisfying about still being able to program TI-Basic via muscle-memory using the token-based input.
- thrtythreeforty 5y ago
  Author here. Great point - I totally forgot to write up CalcNet! It was a protocol designed by KermMartian (DoorsCS guy) for connecting up to 8 calculators to a "local network" of tied-together link ports. There was also bridge software to GlobalCalcNet, which let you sort of VPN your calculator into virtual CalcNet networks over USB.
- ddingus 5y ago
  I get that. Your comments resonate with me. As for the CPU... I paid a few hundred bucks as I put together a great 8 bit workstation and had similar thoughts. We are buying the system. A lot went into these things. A lot can still come out. And the skills can matter to us. Maybe that helps some.
peterburkimsher 5y ago
You're not too old! Embedded systems and home computers grew up together. The TI-84+ that my parents bought me in 2005 was great, especially because my parents paid for it. I feel like any device that becomes popular in schools and is repairable/hackable, will become the platform of the future. The article says "you either knew, or were, that kid" and if you think you were that kid, you probably were. When trying to figure out when embedded systems became mainstream, I accidentally just wrote an incomplete history of embedded pocket computing. 1967: LOGO programming language developed by Seymour Papert. 1970: Sharp QT-8B calculator was the first battery-powered calculator 1972: HP-35 calculator was first scientific calculator 1974: Sinclair Scientific 1974 was affordable, programmable, moddable, repairable. 400 functions in library. 1976: PIC microcontrollers released. 1976: Zilog Z80 launched. 1977: Tandy TRS-80 released, using Zilog Z80 chip. 1977: Apple II released, with colour graphics. 1980: Epson HX-20 released, a laptop with receipt printer and screen. (my dad wrote his Ph.D. thesis on one) 1981: BBC Micro released, targeted at education. 1982: Commodore 64 released. 1984: Apple Macintosh released. 1984: Psion Organiser, 1984 added database, calculator, clock, diary, alarm clock, a-z keyboard. Programmable in OPL, became Symbian. 1985: LEGO/Logo (later Mindstorms) began, with hardware turtles drawing lines using a pen. 1989: Nintendo Game Boy released. 1989: Macintosh Portable released. First laptop with a GUI and mouse (trackball). 1990: ARM founded, as a joint venture of Apple, Acorn (BBC Micro) and VLSI. 1993: Apple Newton 1993 used handwriting recognition, custom ASIC, name PDA. Popular in medical field. 1996: Palm Pilot 1000 in 1996 brought dimensions down to 120x80x18 mm. 1996: TI-83 calculator got added to high school curriculum. 1999: Apple iBook released, targeting education. 2000: Garmin eTrex handheld GPS device introduced. 2000: Nokia 3310 mobile phone released, 126 million units sold. 2001: iPod brought 5 GB disk space, rapidly doubling. Rockbox custom firmware released for Archos in 2002, iPodLinux in 2003. 2004: TI-84 calculator introduced, with USB OTG. 2004: OpenWRT firmware for routers. 2005: Arduino project began. 2007: iPhone decreased disk space compared to iPod but gained capacitive multi-touch screen. 2012: Raspberry Pi released, targeted at education. 2014: ESP8266 released. 2016: iPhone 7 finally exceeded storage of iPod Classic, but removed headphone jack, increased physical dimensions. Embedded hacking involves hardware and software, which makes it hard to specialise. I took LEGO/Logo after school in 2000-2001, then extra ICT classes for IGCSE 2004-2005, then Computer Science for IB 2005-2007, and Electronic Systems Engineering in university 2007-2011. There's plenty more devices and emulators to explore! https://en.wikipedia.org/wiki/Custom_firmware#Other_devices https://en.wikipedia.org/wiki/Custom_firmware#Other_devices

csense 5y ago

The TI Files, where everybody knows your name.

FunnyLookinHat 5y ago

So many fond memories hardware hacking my TI-85. I remember learning to solder so I could add an extra battery pack with 4 D batteries (played too many games!) and writing apps to play music out of the jack. Hacking on my TI-85 and wanting to build websites for gaming guilds (Diablo, Starcraft) is what drove me into computers and software development. There was certainly something unique about that era!

ivansavz 5y ago
I learned to solder for TI-purposes too! Not for battery but to build the 2.5mm-jack-to-serial connector cable (I was too cheap to buy an official one, but successfully wired together the 2-3 resistors and diodes necessary to make the cable work. It was not pretty, but it worked!)
- cyberge99 5y ago
  Same here! I’m going to see if I can find the cable around here somewhere.
- FunnyLookinHat 5y ago
  Oh that's awesome! I still have my TI-89 - maybe I should find some weekend time to do some projects on it... that sounds like a fun one!
- charles_f 5y ago
  Same here! I initially had the cable fit with scotch tape and then later soldered to make it work properly. Also first trip to an electronics store, was terrifying to enter a specialist shop with close to no knowledge

gamegoblin 5y ago

Like many here, I can attribute where I am in life today largely to TI calculator programming. I made many friends on Cemetech with whom I still keep in touch, including a few named in this article. I racked up thousands of posts on the Cemetech and United TI forums and spent countless hours hanging out in the game Blockland which was also popular among those folks in the mid 2000s. To me, one of the most impressive folks in this list is calc84maniac, who joined the scene a year or two after me, but quickly surpassed me in skill, becoming a z80 ASM whiz at the age of ~13 or so, whereas some of the other (very talented) folks were at least STEM university students. I know a few people in this article such as SirCmpwn are on HN, too, so hopefully they chime in this thread. Some of the most memorable things about programming in BASIC on these calculators were the absurd constraints. Your whole program was limited to a few kilobytes. You only had 27 floating point variables, a few lists of floats with a maximum length of 999, no real functions or stack or anything, etc. You’d shave bytes by taking advantage of syntactical quirks that the interpreter happened to accept, like not closing parentheses at the end of a line. I don’t have much of value to add other than expressing some serious nostalgia.

NaturalPhallacy 5y ago
>Your whole program was limited to a few kilobytes. You only had 27 floating point variables, a few lists of floats with a maximum length of 999, no real functions or stack or anything, etc. You’d shave bytes by taking advantage of syntactical quirks that the interpreter happened to accept, like not closing parentheses at the end of a line. I found that smaller programs just ran faster. So I took one I'd written to convert from ASCII strings to binary strings and back. Yes, there's a built in function to do this, but it's very limited. Mine used string representations and so the only limits were memory...Then I changed all the variables to single letters to save space...and rendering the code completely indecipherable in the process. Learning the hard way that "human readable code" is very important at a very young age.
- gamegoblin 5y ago
  One reason for this was that GOTO was a main control structure in TI-BASIC (since it lacked user-definable functions), and AFAIK on hitting a GOTO, the interpreter scanned the program from top to bottom to find the corresponding Label. So it was very easy to write loops than ran in O(program size). This was strong motivation to learn how to use While and For loops.

makeitdouble 5y ago

To stay true to the endless rivalry, here is the HP calculator resources: https://www.hpcalc.org https://www.hpcalc.org Both the TI and HP were tremendously good entry points into programming and, especially for kids who had little interest in or no access to computers.

agumonkey 5y ago
HP RPL is one serious gem. HP48 series had lambda arrow syntax in 1990. << a -> << a a + >> >> All in your jeans pocket.
- peterfield 5y ago
  I was wondering when I'd find this comment :) I was in high school early in the early 90s. I programmed a 2-dice game drinking game on a HP48.
optimalsolver 5y ago
I bet most fans of stack-based languages got their starts on HP calcs.

jurassic 5y ago

TI-83+ played a huge role in my formative years as a programmer/nerd. This was early 2000s. If you like calculators, I also recommend checking out the visual history of vintage TI calculators at http://www.datamath.org/ http://www.datamath.org/

billfruit 5y ago
Please don't take it the wrong way, but by early 2000s PCs were widespread, so wouldn't it have been easier to get into programing through PCs than through these very restricted calculators? I never understand the American fascination with programmable calculators. To me they sound like a racket by calculator manufacturers and education authorities to mandate an unnecessary and expensive device on to students. In many other countries students get through high school and even many undergraduate courses (like CS for example) without needing any calculator at all. Perhaps this is due to the greater focus on analytical problem solving than numerical solutions which is perhaps done in the US?
- yareally 5y ago
  There's a few reasons that only make sense if you were in high school at that time in the United States: - Many schools didn't offer programming courses in the 00s (including mine) - Ti calculators came with a large manual and a list of the keywords/functions built into it - Lots of free time while in high school. Study halls, for example - Sharing apps could be done through plugging a serial cable into two calculators - The calculators were ubiquitous for students - Many of us didn't have great internet at the time, so getting programming resources wasn't easy (manuals, compliers, other tooling)
- jurassic 5y ago
  In the pre-smartphone age, calculators represented the only widely available mobile gaming platform for bored high school kids. That motivated a lot of people I know, including me, to dabble in programming.
- jude- 5y ago
  As someone who cut his programming teeth on TI calculators, I think the fascination from the student side is because it hits a "sweet spot" for casual and budding professional programmers alike: * It's very easy to get started. The built-in TI-Basic interpreter is fully documented in the manual, and is expressive enough to be useful for a wide variety of imminently useful tasks (e.g. writing programs that help you with your homework) without too much of a time investment. Moreover, your math teacher can likely help you, since they probably also write their own TI-Basic programs. * It's a "small" system. You can comprehend how everything in the hardware works end-to-end if you make it to C/assembler programming (doable without professional or academic training). * At the same time, it's a rich and complex enough system that you can make non-trivial games that you and your friends will share and enjoy playing surreptitiously in class. * Everyone you know has one, which means there's a large online presence and user community to help you get started and who will delight at the programs you write. TI calculators precede the Raspberry Pi, smartphones, and netbooks, so there was at one point a "nerdy coolness" factor of having a pocket-sized programmable device you could take everywhere. They were also more affordable than Palm Pilots, and since everyone had one, it was less nerdy to be seen using one in school. Just my two cents.

NaturalPhallacy 5y ago

I sold my first "app" in 1997 for $1. It was a TI-85 program custom written for my chemistry class. It had a couple of minor useful things, but the biggest thing is it would stuff atomic weights into their canonical symbol names in memory, and clear them when you're done to save memory. For example, 2O (two-oh, two Oxygen atoms) was a valid expression that yielded 32. And no, not all of them are available though it's been 24 years so I don't remember which weren't but it was surprisingly few. I thought it would be a immoral to sell something for more than $1, that when I still had it after selling it. I probably could have charged $50. I think I was 16 or 17. But I beat apple to the "$1 app" game by 11 years. And it's part of what made me go into computer science -> programming. I grew up poor, so we didn't have a computer in the house, and no internet either. So I carried around the calculator and it's manual for years in High School.

userbinator 5y ago

The Z80, as well as its contemporary competitor the 6502, are still in production and found as a core in various cheap SoCs for toys and other simple consumer electronics. It's certainly more than enough processing power for a moderately complex calculator, but compare the responsiveness of a TI calculator to the regular Windows (10) calculator running on a machine with several orders of magnitude more processing power --- and the former wins. I've noticed that programmers who have worked with constrained systems and/or started with low-level languages tend to write better code in general (smaller, faster, often both; and less buggy too) by default than those who haven't; I guess the exposure helps develop an intuition for "how much program/computer ought to be enough" to solve a problem.

jdkee 5y ago

Modern RPN calculators (clones). https://www.swissmicros.com/products https://www.swissmicros.com/products

jonathanstrange 5y ago
Unfortunately, only their hardware is modern. :( The software is outdated and too limited. I'm annoyed that HP basically shrunk down their calculator team down to two people or so and that nobody is working on a worthy successor to the HP50g. The HP Prime is definitely not a worthy successor. I especially dislike the incongruent mixture of two different calculator engines, and now they've added Python to their own programming language to make it even more confusing. I guess engineers all use tablets or Wolfram Alpha by now and so they figured there is no market for it.

modeless 5y ago

The magic of the TI calculators is that the hardware is simple in a way no other widely used platform is. Way simpler than something like a Raspberry Pi. No GPU, no BIOS, no PCI, no USB, no kernel. You can directly flip pixels on the screen by just flipping bits in memory at a known address and you can see what keyboard buttons are pressed by reading from another address. And yet despite the utter simplicity, these things are sold and used by the millions even today, so software written for them has a market. I think every CS student should have a chance to program a simple yet real system like that.

divbzero 5y ago
I wish someone had explained the mapping of memory to input/output to me in high school. Had I known it was so straightforward I would have ventured beyond programming BASIC on the calculators.
thrtythreeforty 5y ago
Agree, the system is uniquely approachable for low level. The simplicity is beginning to be a problem for Texas Instruments who faces competitive pressure from other companies who have a more modular codebase and can just drop in Python support. TI is heavily invested in their z80 assembly codebase and can't get things like CircuitPython to build on ez80, leading to hacks like shipping a totally separate ARM microcontroller to run the Python environment, with the z80 playing dumb terminal. A smarter solution would be to virtualize the z80 portions on basically any other architecture and slowly start moving to C wrappers for TI-OS functionality.
userbinator 5y ago
They do have a ROM, but it's basically equivalent to famous 80s home computers like the C64 and ZX. Also early games consoles like the NES (which truly doesn't have any ROM---it's all in the cartridge).

billfruit 5y ago

I never understand the American fascination with programmable calculators. To me they sound like a racket by calculator manufacturers and education authorities to mandate an unnecessary and expensive device on to students. In many other countries students get through high school and even many undergraduate courses (like CS for example) without needing any calculator at all. Perhaps this is due to the greater focus on analytical problem solving than numerical solutions which is perhaps done in the US? (Reposting this as a direct comment, after posting as a reply a comment below.)

searchableguy 5y ago
Which country are you from/talking about?
divbzero 5y ago
Is the US really the only country where programmable calculators are used heavily in high school math classes?
- eliasson 5y ago
  No, these calculators were fairly popular in Sweden as well (at least during the late 90s).
- pjmlp 5y ago
  In Portugal we used them as well, but we don't suffer from a TI monopoly on the education system. Anyone is free to pick whatever they wanted, so we had a mix of Casio, TI and HP calculators. The Casio Basic tablets were the most famous ones, FX-850P. https://en.wikipedia.org/wiki/Casio_FX-850P https://en.wikipedia.org/wiki/Casio_FX-850P I eventually had the follow up model FX-880P, after using FX-4500P during high school. https://www.casio-calculator.com/Museum/Pages/FFF/FX-4500P/Casio%20FX-4500P.html https://www.casio-calculator.com/Museum/Pages/FFF/FX-4500P/C... https://www.casio-calculator.com/Museum/Pages/FFF/FX-880P/Casio%20FX-880P.html https://www.casio-calculator.com/Museum/Pages/FFF/FX-880P/Ca...
toast0 5y ago
Sure, they're a racket. But they're also a handy tool. You can plug in a bunch of arithmetic, and it just does it, but you can easily edit and redo. They can graph some functions, and do some of the brute force stuff (like newton's method etc), so you can concentrate on the thinking. If you spend the class time writing a program to solve the homework, instead of doing the homework, you've practiced a life skill and probably understand the material pretty well. If you get the 68k based calculators (ti-92 and ti-89), they've got a symbolic algebra system and can do a lot of cool stuff, although giving that to a high schooler may not be the best choice.

DavidPeiffer 5y ago

Since we're swapping TI calculator stories... In 8th grade Geometry class circa 2007, I had an awesome teacher and loved the subject. I found an extra TI-83+ laying around the house from my brothers. I found a guide online and started building simple programs. A few weeks later, there was a quiz. I asked the teacher if it was permissible to use calculator programs on the quiz. He thought a moment and said it was fine as long as I wrote them myself. So I wrote a very simple program that probably did little more than guide which formula to use in a basic decision tree. It was the hardest quiz of the year, it was just difficult content. My class has 1 A, 1 B, 1 C, and about 23 F's. I was the B. After that, graphing calculators weren't allowed. Mad respect for Mr. Gass. He had two Apple IIe's and had programmed Wheel of Fortune and Jeopard! for review days ahead of tests. He had a couple TV's around the classroom so everyone could see the game well, and would turn on Bill Cosby during some working sessions because at the time, he was a well respected man. Mrs. Gass was also a math teacher. Some students who had both teachers made shirts which advertised "I passed Gass twice"

nicolas_t 5y ago
> So I wrote a very simple program that probably did little more than guide which formula to use in a basic decision tree. > It was the hardest quiz of the year, it was just difficult content. My class has 1 A, 1 B, 1 C, and about 23 F's. I was the B. Slightly out of topic but one of the most bone headed decisions I've seen politician do is banning the use of custom software during exams. In France, they created a law forcing all programmable calculators to have an exam mode, during exams (including the national baccalauréat), the calculator needs to be in an exam mode with a special blinking light appearing and during which time students are not allowed to access programs. What I liked when I was a child about the exams in France is that they tended to be difficult without multiple choice questions and needing students to master the material, With such exams, having previously stored the formula in a calculator is of little value and so this anti-cheat mode doesn't help. It's also a more realistic example of real life when we all have access to Google, yet just having the answer doesn't make all of us doctors, mathematicians, engineers or lawyers. On the other hand, creating useful little programs to help verify things has value, it helps with learning, it gives motivations to kids to learn how their calculator work and is a great way for kids who are mostly exposed to lockdown platforms to start programming.

bane 5y ago

The TI calculators have ended up serving American students in a similar way the BBC Micro served British students and now how the Raspberry Pi is serving everybody. "Cheap", ubiquitous, hackable, easy to understand computers. Many of the developers I know can think back to the first computer they ever wrote a program for, but if you press them, they'll often realize that they actually first wrote software for the TI calcs. https://ticalc.org/ https://ticalc.org/ is a treasure of the internet.

ticalc-isaacs 5y ago
> https://ticalc.org/ https://ticalc.org/ is a treasure of the internet. Thanks! (I founded ticalc.org back in 1996.) While calculators weren't my first programming experience, starting ticalc.org was formative for me. Getting all the TI hobby site maintainers (and ZShell developers) involved, registering the domain, setting up the server (Slackware!), etc. really led to my career in tech. While I regularly encounter new technical challenges, almost every organizational challenge I've ever encountered as a technical leader since has had precedent from working on ticalc.org. I do wonder whether and how ticalc.org should evolve now. Traffic and activity peaked before smartphones became ubiquitous (for obvious reasons) but it's still pretty popular - See https://ticalc.org/about/webstats.html https://ticalc.org/about/webstats.html. We've always been strictly non-commercial and I don't envision changing that (mainly because I believe in our all-volunteer public service mission, but also because any serious encounter with bureaucracy would probably be fatal for the project.) But I am thinking about succession - what happens when our active staff no longer have the time or energy to maintain it. I wonder if HN'ers with comparable experiences with long-running volunteer projects like this have some wisdom on this topic?
- bane 5y ago
  I have no particular advice for you, but greatly appreciate the site and all the fun and utility I received from it. At the very least you might want to consider periodic snapshots of the site and all the software be put up on archive.org.
- thrtythreeforty 5y ago

continuational 5y ago

Fond memories! I wrote this little game in z80 assembler in highschool: TI Slimeball: https://www.ticalc.org/archives/files/fileinfo/290/29096.html https://www.ticalc.org/archives/files/fileinfo/290/29096.htm...

mikeknoop 5y ago
That’s cool! I also made a version of this game around the same time: https://www.ticalc.org/archives/files/fileinfo/248/24890.html https://www.ticalc.org/archives/files/fileinfo/248/24890.htm...
Jyaif 5y ago
Slimeball! I wrote a TI89 version: https://www.ticalc.org/archives/files/fileinfo/340/34000.html https://www.ticalc.org/archives/files/fileinfo/340/34000.htm...
NanoWar 5y ago
I played it back then. Thank you!

dietrichepp 5y ago

There was a puzzle game I had for the TI-86 called simply “dstar”. I always wondered who made it. When I looked it up, it looks like it was based on an HP-48 game by the same name. I’ve ported it to JavaScript, and it runs in the web browser. I also added the ability to show the solution to each level, and skip to any level. https://www.moria.us/games/dstar/play https://www.moria.us/games/dstar/play

zerocount 5y ago
Just played it and it's a lot of fun! Thanks for sharing the link.

distantaidenn 5y ago

Ohh, TI stories! Here we go! "Hey, distantaidenn, I wanna talk to you after class." These were the words of my then high school math teacher. I wasn't worried, I was a good student. Little did I know, this would shape my career for the next 20 years. When after class came, my teacher handed me a brand spanking new TI-83. "We're gonna be using these in class from now on. Take this home for the weekend, learn how to use it, and teach the rest of the class." I held in my excitement, and took the device, along with its 1-inch thick manual. I pored over the manual. Before I knew it, I had mathematical functions dancing across the screen. All of our current math equations set up to accept variables and spit out answers. I didn't know it at the time, but I was "programming." I began to dabble in TI-Basic -- I had no idea what it was, but apparently, it was the language this giant calculator used, and I'd have to learn that language to make this machine do my bidding. So I learned it. The next year in school, I signed up for an elective Programming class, and lo and behold, it was in Basic -- I thought to myself, this looks familiar, I know this! I finally made the connection that I had been "programming" the whole time. From then I was hooked. Fast forward to university, I gained a degree that was as far from programming as possible, but I always had my scripts. I was the guy that could talk to computers. I was at home on the command line. And I knew enough html and JS to make a shitty web page, if necessary. And here I am now, still engineering and managing, and making (I'd like to think) not so shitty products for a living.

BigHatLogan 5y ago
Great story--thanks for sharing! It's interesting how the unexpected, serendipitous moments can have such downstream effects on our lives! Just out of curiosity: what did you end up studying in university? And how come you didn't study computer science / programming despite acquiring an interest for it earlier in your life?
- distantaidenn 5y ago
  Thanks! I decided to delve into the "pure" sciences of mathematics and physics. I figured I'd end up in the ivory towers of academia. And of course, like many other undergrads, I ended up major hopping a bit. I never considered programming as a career until it happened.

DamnInteresting 5y ago

So many whipper-snappers here talking about their TI-83+ and later models. When I was in high school ca. 1994 my trusty TI-82 kept me quite busy writing BASIC games. We used to share games with the data sharing cable, I wonder if any of mine still survive somewhere. I still have the physical calculator tucked away in some box, but it is certain that the batteries are long since dead, and all of the volatile memory faded away. In high school, my calculus teacher discovered that I had written programs on my TI-82 to help me solve homework questions. Much to my surprise, he approved! He explained that his objective was to teach us to solve the problems using whatever tools we had at our disposal—writing a BASIC program to solve the problem was not cheating, rather it was making the best of my resources.

tgv 5y ago
I honed my skills on a TI 58. What a machine. I wrote a simple 8 queens solver, which took nearly 30 minutes to reach the first solution. Great times.
- dboreham 5y ago
  Seeing the headline I came here thinking I'd read about TI-58/59 hacking. I actually had no idea there was a whole later generation of TI calculators based on the Z80! I spent endless hours messing around with my Dad's TI-58 in 1977 and recently bought two examples on a popular online auction site to preserve for when I have that kind of spare time again.
dubbel 5y ago
Same here! I had to "delete" my programs though (I think I was able to hide/archive it and restore it after the teacher had checked my empty program list... or did I write an emulator of an empty programs list? I can't remember). I also wrote the first TI-BASIC tutorial in German on my first blog as a high-schooler. It got pretty popular with it's target group (other high-schoolers who were bored in Math class), and 12 years later I got an email by an unknown person who had randomly stumbled upon my blog again and thanked me for writing it. That one email had been enough to make it all worth it by itself. Edit: Here it is: https://archive.haukeluebbers.de/ti-basic-tutorial/ https://archive.haukeluebbers.de/ti-basic-tutorial/

mikeknoop 5y ago

Learning to code and hack on TI 83+’s definitely has through lines to my career nearly 20 years later. One thing I’m particularly proud of was figuring out how to build an Assembly program workaround for TI’s “testguard” (a tool to force clear someone else’s calculator memory via link cable) in middle school: https://mikeknoop.com/upload/SafeGuard.zip https://mikeknoop.com/upload/SafeGuard.zip

mbg721 5y ago

Never underestimate a bored person with something that looks to their boss like work.

bo1024 5y ago

I'll also chime in. Early in high school, went from writing one-line basic programs to reading the assembly and C source code of Phoenix and other games. Wrote some games of my own in C and assembler. Now pursuing a career in CS. A very strange entry point in retrospect, but such a serendipitious one.

tablespoon 5y ago

> In the mid-to-late 2000s, you either knew, or were, that kid in grade school. You know. The one who could put games on your graphing calculator. Nit: That was totally a thing in the 90s as well. In junior high, some (actually pretty non-techie) kid knew (I think) a college kid who installed ZShell (http://tistory.wikidot.com/zshell http://tistory.wikidot.com/zshell) and some games on his TI-85. Pretty soon everyone else got them via memory backup. Eventually those got boring, and I was the kid who got the Graph-Link kit to get new game. This article actually seems to be kinda unaware of the earlier phases of this subculture, that were centered on the TI-85/86 and TI-92/89.

lambdaloop 5y ago

Ah I was so into writing TI-BASIC (and eventually, experimenting with z80) on my TI calculator! I would be carrying it to every class. This was before smartphones and I had a lot of times where I had nothing better than to write program on the calculator. I wrote so many things, like a hangman game (with a wide vocabulary) and an RPG fully in TI-BASIC, with a 2D map and a combat system. You could store only a limited number of pictures, so I made up a format for mapping pictures into strings, with a corresponding encoder and decoder. My favorite program I wrote is ELIZA, a copy of the famous therapist AI program (actually inspired by the alt-text of the xkcd linked in the article!). It had like 30 rules or so and worked remarkably well, to the extent that I would talk to it often through my problems.

ecpottinger 5y ago

AAAARRRRHHHH! Reading the link I saw the solution I missed decades ago when I tried to use POV to make my PET create a colour display. Just reading the section on how they did 4 levels of grey scale was an eye opener. Yes, I got some colour by flashing squares on and off but it was unwatchable. I did the flashing for the entire screen together! Just by breaking up which squares flashed at different times I can now see would have made a big difference. Almost 40 years to learn what I did wrong.

sbrother 5y ago

Oh man, getting obsessed with TI-82 BASIC in middle school is definitely the reason I have the career and life I do today. I remember after years of dealing with ~36 variable slots and all the other insane limitations, my parents got me a TI-89 for Christmas and it changed everything. You could perform "indirection" on a constructed string, which opened up all kinds of awesome techniques. And you could draw lines and points on the canvas! I built an incredibly slow pokemon clone and a theorem prover before a kind mentor suggested I try programming on the computer. I hope these sorts of experiences will still be accessible for my kids. Having a school-mandated device with a button labeled "PROGRAM" that took you straight to a BASIC interpreter made it possible for someone like me, growing up in a rural area with zero parental technical knowledge, to end up where I am today.

hutzlibu 5y ago
"I hope these sorts of experiences will still be accessible for my kids. " If they surfe the web from their computers, they are just a click away, from a WebIDE, called dev tools, much more powerful, and millions of tutorials how to use them. Thd opportunity they have.

stkdump 5y ago

I used tigcc to write a program that can draw the root locus (https://en.m.wikipedia.org/wiki/Root_locus https://en.m.wikipedia.org/wiki/Root_locus). I had a version that ran in ti basic at first, but it was too slow because it had to solve a polynomial (order 3 or 4) per pixel. It was my way of cheating, because the calculator was allowed in most exams. I considered it not quite cheating, because I figured being able to code the solution should also count. I also coded up ti basic programs that instead of just spewing out the solution to some types of maths problems also gave the steps. That saved a lot of time in maths exams so that I had more time for the problems that required more thought.

johnebgd 5y ago

Finished high school in 2003. Was told to pickup a graphing calculator in 6th or 7th grade. My family bought me a second hand TI82. I might be the only student to have had one malfunction but the = button stopped responding that first year. My family got me a TI83 after that. I would later buy myself a TI83+ when I started working part time. That was my first exposure to basic. I would like to believe I am also still the record holder for an uncle worm high score.

znpy 5y ago

I went back to school and was thrilled to have an excuse to use my ti86 once again :) Love that thing.

m0ngr31 5y ago

I was the same way but with Casio calculators. Got me into programming and the casiocalc.org forum was the first online community I was ever active on. It's like a ghost town now but it was a good time back in the day.

jpatte 5y ago
Same here. The "Casio hackers" community was nowhere near as large as the TI folks, but we had some good times and some impressive projects too. :)

deleted 5y ago

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em3rgent0rdr 5y ago

Fond memories myself of writing a texture rotator/zoom demo and squeezing every clock cycle out of it.

wiz21c 5y ago

I found this which has some screen shots : https://www.youtube.com/watch?v=Jo_WgbUfNxc https://www.youtube.com/watch?v=Jo_WgbUfNxc

gambiting 5y ago

Well, I'm jealous of you Americans being allowed graphing calculators. As someone who went to Polish shools in the same period of time, only basic calculators were allowed(addition/multiplication/subtraction/division and nothing else). I've had a graphing calculator but it was just a novelty to play with at home since it wasn't allowed at school.

inglor_cz 5y ago
I passed through Czech schools with my second-hand TI-83 calculator. They only probably found out what it can do afterwards. That second-hand TI-83 cost me like half of average salary (in 1994), but it worked really well. I still have it, but I no longer have any use for it.

thewakalix 5y ago

> This is not a coincidence because nothing is ever a coincidence with xkcd. I love these little in-jokes.

thrtythreeforty 5y ago
Haha I am glad someone noticed :)

ttoinou 5y ago

I started programming because I was bored in school at 13 yo and using a TI 83 was accepted in almost all classes. I coded a dichotomic number guesser, Collatz path grapher, unbeatable tic tac toe, minesweeper with recursive finding of surrounding blank cells, IFS (iterated function system) grapher generated from random points (to draw fractals), a Connect Four etc. All this with a 6 lines screen and a huge amount of noise around me constantly. When I got home, I would link the TI on my computer and install a copycat of Pokemon Blue/Red for GameBoy that someone coded in assembly and realize how awesome some others people were, and I had still so much to learn

Foobar8568 5y ago

I remember playing "Zelda" clone on my HP48GX back in the late 90s, what an era and impressive feat. And if I am not wrong, a lot of today CAS solvers on calculators are derived from https://www-fourier.ujf-grenoble.fr/~parisse/giac.html https://www-fourier.ujf-grenoble.fr/~parisse/giac.html and from the author of the famous Erable (Mapple in French :o )

lawl 5y ago

The guy that developed the gameboy emulator mentioned in the article is now working on a new version that jit-recompiles gameboy roms: https://github.com/calc84maniac/tiboyce/tree/dev https://github.com/calc84maniac/tiboyce/tree/dev

crocal 5y ago

Dude. TI-81 was my high school calculator. I got pretty famous at some point for managing to squeeze into it a decent RPG with monsters, health points and some story line. Other geeks were jealous and jocks patted me on the back for providing distraction. The challenge was the available BASIC program memory. We spent the next few months figuring out how to reduce the footprint to the bare minimum to add more gameplay. No internet at the time. Just our brains and the manuals. I chuckle at the idea of what we could have done if we had been hinted access to assembly and pixel flicker tricks to have 4 colours. EDIT: Typos

yrcyrc 5y ago

Circa 1995/6 was it for me but on Casio calculators [1] There were books devoted to it, I was able to program games, school cheat notes, brilliant memories. [1] https://fr.wikipedia.org/wiki/Casio_CFX-9960GT https://fr.wikipedia.org/wiki/Casio_CFX-9960GT

shmageggy 5y ago

It appears Durk Kingma, the author of the greyscale library mentioned, is renowned AI researcher http://dpkingma.com/ http://dpkingma.com/. Pretty neat.

stephc_int13 5y ago

My first big project was also done on a similar calculator. A few years before the TI era there was a strong HP-48 scene in France and I believe that many of the early work and games on TI-8x and T-9x were inspired by what was already available on HP-48. Here is my own contribution at the time: https://www.hpcalc.org/hp48/apps/shell/ https://www.hpcalc.org/hp48/apps/shell/ A multitasking alternative OS and a few apps, I learned a lot working on this.

jaco8 5y ago

All this brings up long subdued memory .... my HP-25 ,which had cost me one months work during school holidays.. I still remember when I got payment and the next day walked into the shop and told the perplexed salesperson : I want this! He thought nobody in his right mind would buy a calculator without an equal sign button. Anyway I used it from 1975 to abt 1993 when the battery leaked .

samgranieri 5y ago

The first program I wrote was a quadratic equation solver on my TI82 in the mid 90s. I bought the link cable and enjoyed playing assembly games on my TI86.

trackrn6 5y ago

Before iPads were commonly used while flying. My first program was setting up an app to calculate wind correction and fuel estimates into my TI-83. It was the first time I was able use Trig and programming to solve a real world problem.

ChicagoBoy11 5y ago
hahah that's awesome! Makes me wonder now if anyone ever took a checkride and instead of an e6b just whipped out a TI83 in the middle of it. I'd pass that guy instantly! hehehehe

ChicagoBoy11 5y ago

I'll never forget this project a friend and I worked on because of the "clear your devices" procedure they had us do before every test to make sure we weren't cheating or something. At that point we could archive things and whatnot, but it was just a PITA to deal with it and we kept getting annoyed at having to clear our calculators. So then, of course, we made our own program that would simulate the memory cleared screen, and we used it successfully. Of course, we got paranoid lest anyone would find out, so we ended up just adding to it, so you could then interact with the calculator and even do math on it, so it wouldn't seem like you were interacting with our program. Funnily enough neither of us ever came close to using it for cheating -- I mean, we didn't need it. But I maintain that in the couple decades since, it was probably some of my best work.

h0nd 5y ago

My first few basic lines of code were written on a TI83+. Nostalgia.

gorkish 5y ago

Though I have absolutely no proof of it since that era is both a black hole for usenet and before calc-ti.org, I believe I can claim to have published the first fake-grayscale demo in asm for the TI-85. This would have been in maybe 1993 or 1994 I think. It was a 4-frame animation of Bevis and Butthead headbanging, and since it was essentially stored as 16 uncompressed bitmaps, it took the calculator's entire memory. Getting grayscale out of a mono LCD was obviously not a unique idea, but at least I independently arrived at the notion that it could work. I hammered out the TI-BASIC version and proved it sorta worked, but only if I could make my program run fast enough. I should mention that I was 12. Before zShell existed, my only programming as a kid had been things like BASIC and Logo; the closest I ever got to anything more fun was some type-in programs that used a whole lot of opaque POKE and PEEK statements, and I got frustrated trying to get C64 programs I got from a book at school working on the Apple ][. I was shit at porting software in middle school. Going from this straight to z80 asm was insane, but the naivety of youth gave me confidence. My programs would be harder to write but they would run faster. Naturally the fastest program would be the hardest to write, so z80 asm it was. I was hooked. I became a software developer. I remember specifically in those early days emailing with Magnus Hagandar, Dan Eble, and Mattias Lindqvist. Thanks to each of you and to all the other early TI fans who helped me along and put up with me. In later years I learned most of this community were also basically kids playing adult on the early Internet. What a time it was!

jeffalyanak 5y ago

https://www.irrlichtproject.de/houston/ https://www.irrlichtproject.de/houston/ Houstontracker 2 is a surprisingly powerful music software for TI calculators which accomplishes its magic by bit-banging the serial data port to produce stereo audio!

davegauer 5y ago

The first piece of "real" software I ever wrote was called "DISC" because it's initial feature was printing out the discriminant of a parabola. But I added to that program as the high school algebra class continued so that by the end of the class, it could spit out answers to all sorts of problems. Everybody loved it. A fellow student assumed the name stood for "DISCovery", so I retroactively made it so. After that came a little text-based adventure game that made the rounds. And then what was to be my magnum opus: a graphical adventure with locations you could select with a "mouse" cursor controlled by the arrow keys. Everything was first plotted out on graph paper and hand written because it was actually FASTER TO WRITE TI-BASIC ON PAPER than entering the program using the calculator keys. I had overcome the biggest technical hurdles and it was looking great when, for some reason, I decided to change the AA batteries AND the coin cell battery at the same time. Everything else was backed up to friend's calculators. But not that graphical adventure game. It was gone as soon as that coin cell came out. I did not have the heart to re-enter the program and the school year was ending anyway. I still remember that sinking feeling when I realized my work was lost.

matyo91 5y ago

Hi ! This article tell a lot from me. Have a look at all my TI-89 programs I developed at high-school. https://apps.darkwood.fr/ti89 https://apps.darkwood.fr/ti89 Was good time !