[HN Gopher] TI-83 Plus One More
       ___________________________________________________________________
        
       TI-83 Plus One More
        
       Author : rez10191
       Score  : 123 points
       Date   : 2022-07-31 13:20 UTC (9 hours ago)
        
 (HTM) web link (www.leadedsolder.com)
 (TXT) w3m dump (www.leadedsolder.com)
        
       | iasay wrote:
       | I have done many a repair with kynar wire like this. I am not
       | proud of most of them but they worked afterwards.
        
       | libertine wrote:
       | I always wondered what are the margins for this product, it's the
       | same product for decades, and the price tag remains high.
       | 
       | The cool thing is that it can be passed on younger generations.
        
         | Tijdreiziger wrote:
         | https://xkcd.com/768/
        
       | Aissen wrote:
       | > Over the course of several decades, they must have been making
       | a large integer multiple of the build cost in pure margin while
       | not updating the product.
       | 
       | Yup, this is an open secret about calculators: they are basically
       | regulatory capture nowadays, since you can buy much more powerful
       | devices for cheaper. Software used to be an advantage, but the
       | algorithms they use are now common knowledge.
       | 
       | You can also use an alternative like NumWorks, that has source-
       | available software and lets you run your own code; they have
       | played the regulation game and have a reset button that allows
       | them to be used at some exams in France, Italy, Netherlands, some
       | US states, etc.
        
         | gamerDude wrote:
         | Most of the schools I work with now have their students use
         | Desmos, a free online graphing calculator. So thankfully, we've
         | been moving away from TI.
        
         | sascha_sl wrote:
         | In some states of Germany they also lobbied for advanced high
         | school courses to require a Voyage 200 (after you already
         | shelled out for a TI-84+). This thing was pricy and the school
         | ended up having a few units to lend out because not everyone
         | could afford them.
        
         | int_19h wrote:
         | There's one thing that calculators can do that powerful modern
         | gadgets cannot: run on AAA batteries.
         | 
         | It doesn't even have to be something as old as TI-83, too. For
         | example, Casio Prizm FX-50 has a color screen, and can be
         | mounted over USB as a storage device. And in terms of hardware
         | power, it's fast enough to run a NES emulator:
         | https://github.com/tswilliamson/nesizm.
         | 
         | (For the curious, here's a dev wiki for this platform: https://
         | prizm.cemetech.net/index.php/Prizm_Programming_Porta...)
        
         | modeless wrote:
         | It is a shame that calculators are stuck in the past for silly
         | regulatory reasons, but there is a silver lining. These relics
         | are excellent machines for learning low level programming
         | without the complexity of modern hardware. You can write C code
         | with essentially no operating system underneath you, read the
         | keyboard I/O registers directly, flip pixels on the screen by
         | writing to the framebuffer pointer, write your own interrupt
         | handlers, etc. There are no other widely available computers
         | this simple anymore, and because of their ubiquity there is
         | still an active hobbyist community making new software.
         | 
         | If I was going to make a course on programming I would get
         | every student a calculator and have them write some C on it.
        
           | Nav_Panel wrote:
           | Yeah, absolutely. I learned to code in middle school in TI
           | Basic during math class (much to my math teacher's dismay),
           | writing little platformer games as a snarl of GOTOs and pixel
           | on-off (because the more robust drawing functions weren't
           | fast enough to do real-time gameplay/animation). Impossible
           | code to read, but I had a lot of fun.
        
           | TimTheTinker wrote:
           | > there is a silver lining. These relics are excellent
           | machines for learning low level programming without the
           | complexity of modern hardware.
           | 
           | My thought exactly. Give kids a calculator app for their
           | phone, and I'm positive far fewer would end up writing code
           | for it - and fewer would end up as developers.
           | 
           | There's something _so cool_ about writing a little game and
           | showing it to your friends when you 're in 9th grade. "Dude,
           | you programmed a game on your calculator?! You're a genius"
           | is so fun to hear at 14 years old.
        
             | zerocrates wrote:
             | Do you have any knowledge whether there's still much of
             | this going on?
             | 
             | I remember futzing around with TI Basic and
             | downloading/sharing more complex games from others... but
             | we didn't have smartphones then. I just wonder to what
             | extent students still care about that stuff today.
             | 
             | I suppose there's still some appeal from the "look like
             | you're doing work" factor if nothing else.
        
               | morninglight wrote:
               | The Raspberry Pi Pico has opened the door to young
               | experimenters thanks to the MMBasic programming language
               | from Geoff Graham. There are several excellent videos
               | that explain the setup and operation. The Pico is
               | actually available for $4. The software and manual (PDF)
               | are free to download. It is super easy to get started - 5
               | minutes and you're writing software that can solve
               | problems and control I/O.
               | 
               | PicoMite: Running BASIC on a Raspberry Pi Pico
               | 
               | https://www.youtube.com/watch?v=Cxmjy1nz6MM
               | 
               | PicoMiteVGA Raspberry Pi Pico Running BASIC on VGA
               | 
               | https://www.youtube.com/watch?v=gIK1ujslHHI
               | 
               | ....
        
               | pfyra wrote:
               | Yes yes, but the pico is a lot harder to program during
               | class while looking like you are doing school work.
        
               | BoorishBears wrote:
               | It's funny reading this thread where everyone is leaning
               | towards "those dang kids and their smartphones are
               | missing out" while ignoring things like Roblox, where
               | entire economies are being built of the creativity of
               | kids
        
               | morelisp wrote:
               | I don't want economies, I want kids to have genuine,
               | self-directed creative outlets. _At best_ today Roblox is
               | baby's first hustle culture.
        
             | radicalbyte wrote:
             | Looking on Amazon... TI calculators are running Python
             | nowadays. Much easier to understand but C would be a much
             | better introduction to computing for them :(
        
               | modeless wrote:
               | TI has never supported C on its calculators. That's part
               | of the fun :)
        
           | saagarjha wrote:
           | Writing C for the TI-83+ is generally not a very pleasant
           | experience. Now, for the m68k TI-89, that's a different
           | story.
        
             | ska wrote:
             | Could be worse, the contemporaneous up-market option was
             | still HP at the TI-83 time, no? In that case if I recall
             | correctly your only options were reverse polish lisp and
             | assembly...
        
           | christkv wrote:
           | I plan to check out https://www.aoz.studio/ its by the guy
           | who wrote the legendary AMOS games programming software for
           | the Amiga and looks a fun way to teach programming
        
           | undersuit wrote:
           | I learned how to program basic on my 83 over a weekend
           | between my track and field events. Made the calculator much
           | more usable.
        
           | omginternets wrote:
           | Damn, that would be incredible. Any chance you'd consider
           | making a YouTube series?
        
         | ruph123 wrote:
         | The NumWorks calculator looks very interesting. Too bad it does
         | not have a RPN mode.
         | 
         | Otherwise the SwissMicros calculators can be recommended. They
         | are all RPN and are modeled after iconic HP calcs. They are
         | just very pricey, especially for non-graphing calcs.
        
           | ranger207 wrote:
           | The Omega alternate firmware does have RPN
           | 
           | https://getomega.dev/
        
           | LEARAX wrote:
           | My DM42 broke in under 2 weeks and Swissmicros support was
           | completely unreachable. I would strongly recommend getting a
           | used older HP calculator instead.
        
             | ericvsmith wrote:
             | I had the exact opposite experience. After already owning a
             | DM42, DM41X, and a DM16L, and I bought a DM12L for a
             | client. The screen had several LCD segments that faintly
             | showed as always on. I wrote an email and was contacted by
             | Michael (the founder) almost immediately. He said they'd
             | happily take it back and send me a new one, but it would
             | take a few weeks for shipping from Europe. Instead he
             | suggested that I first try putting it in the oven at 70C
             | (160F for us 'Mericans) for a few hours. So I disassembled
             | it and put just the PCB/display unit in the oven. And sure
             | enough: problem solved!
             | 
             | tl;dr: I thought their service was great.
             | 
             | Although I do love my real HP's, too. I own maybe a dozen.
             | I think the 32sII is my favorite, but I dearly miss my 41CV
             | from back in the day. Maybe I should find a used one of
             | those.
             | 
             | On the programming side: I definitely agree with those
             | saying calculators were/are an entry to programming. My
             | first programs were on an HP-29c. I thought I had invented
             | binary search!
        
         | projektfu wrote:
         | I had the privilege of buying two expensive calculators. First,
         | a TI-85 (1993) and then a new math teacher hired was more
         | familiar with the HP-48G (1995) and had us get one. While fun
         | to use to goof off in class, I felt they were like learning to
         | use a slide rule: obsolete before you bought them. Did the
         | small screen and the over-precise numeric answers give us a
         | better idea of what we were doing than pencil and graph paper?
         | Did it make any students appreciate math subjects more?
         | 
         | Having built an RPN evaluator at summer camp, I appreciated
         | that my friends were learning it, too, on the HP-48.
         | 
         | In college, I literally never used it. A simple scientific
         | calculator was almost always more useful.
        
           | petee wrote:
           | I'd argue that a sliderule is at least something you can
           | manipulate with your hands and immediately see the output
           | relationship.
           | 
           | Tangent, I use a tape measure at work and you can fold it
           | back on itself to make a basic slide rule for quick addition
           | and subtraction without bothering with fractions :)
        
         | twobitshifter wrote:
         | Mine was a hand me down from my older sister. Our public school
         | did have some TI-82s that they lent out for classes, but that
         | wasn't always the case and the cost of a calculator was
         | certainly a burden on some families.
        
       | siraben wrote:
       | I've owned a TI-84+ calculator since around middle school (they
       | are priced ridiculously everywhere on the planet, and this only
       | exacerbates the problem because of purchasing power differences).
       | However, it can provide a unique programming environment that
       | rivals modern setups with a lot of learning potential (perhaps I
       | would recommend NumWorks these days, but it's still $100.)
       | 
       | One of the earliest programs I wrote in middle school was a
       | program to solve quadratic equations given the coefficients, then
       | a program to compute the golden ratio by iterating the function
       | f(x) = 1+1/x, and a Langston's ant program (all written in TI-
       | BASIC on the device itself, with zero setup necessary.)
       | 
       | Later on in high school (late 2010s) as I learned C programming
       | and data structures on my own, I read "Learn TI-83 Plus Assembly
       | In 28 Days"[0] and got into assembly programming, eventually
       | culminating in a Forth-based operating system[1] that runs from
       | boot. You do need to have a computer for this setup, but the
       | calculator comes with a cable in the box. It also was not
       | uncommon to see other high school students download games or do
       | light forms of hacking (mostly centered around storing data to be
       | retrieved during exams.)
       | 
       | Contrast this to if you wanted to do assembly programming on a
       | modern computer and understand the boot processes of your
       | machine. It's significantly more complicated that even at the
       | university level it is not taught in detail. The boot process[2]
       | or memory mapping[3] for the 84+ can be understood relatively
       | easily, and the assembly instructions are much simpler.
       | 
       | While I similarly lament the price point, the fact that you have
       | essentially given/required the purchase of a standardized, self-
       | contained, non-trivial computer to students could potentially be
       | used to teach programming and computer science from an early age.
       | 
       | [0] https://tutorials.eeems.ca/ASMin28Days/lesson/toc.html
       | 
       | [1] https://github.com/siraben/zkeme80
       | 
       | [2]
       | https://wikiti.brandonw.net/index.php?title=83Plus:State_of_...
       | 
       | [3]
       | https://wikiti.brandonw.net/index.php?title=83Plus:Memory_Ma...
        
       | glitchc wrote:
       | I did the same fix for my mother-in-law's calculator. She teaches
       | high school kids and this is her mainstay. Of course one day it
       | got the dreaded disappearing rows (where two or more rows go
       | dead), and this was the fix someone recommended on the forums.
       | 
       | Now my own 83 is in the same state. Although I have a Ti-89
       | kicking around, I still miss the ergonomics of the 83.
       | 
       | All in all, wanted to say thanks for the writeup.
        
       | rwmj wrote:
       | The vias are there in order to connect different "islands" of the
       | ground plane together I think. (Not literal disconnected islands,
       | but you generally want ground planes on different layers to be
       | connected as much as possible).
        
       | marwatk wrote:
       | Tangentially related, I just finished porting wxWabbitemu (TI
       | calculator emulator) to WASM last week [1]. I recently switched
       | to iOS from Android and sorely missed the TI emulator app. I use
       | my TI-85 from high school as my desk calculator and the primary
       | calculator on my phone.
       | 
       | The UI is meant for cell phones, I don't have a max-width set so
       | it looks funky on a full desktop browser.
       | 
       | [1] https://marwatk.github.io/wasmwabbitemu/
        
       | jamesliudotcc wrote:
       | My high school basically expected you to get a TI 83. My dad
       | decided that it was a ripoff and we got Casios instead. Casios?
       | Oh, nothing survived in my backpack. Nothing, so Casios.
       | 
       | Eventually my school got around to issuing me and my acadec
       | teammates TI-89s.
       | 
       | Looking back, I still think the most useful aspect was being able
       | to see what calculation you typed in, so you could check for
       | typos.
        
         | erhsfhgvz wrote:
         | similar situation, but in my case the school wanted everyone to
         | have a TI-82. when we went to walmart, they were out of 82s, so
         | my folks splurged and bought me an 85 without knowing the
         | incompatibilities.
         | 
         | not being able to link with peers and teachers sucked, but that
         | calculator gave me my first taste of hardware -- building a pc
         | link cable by cramming two diodes and half a link cable into my
         | pc parallel port, and first taste of z80 assembly
        
       | dbecks wrote:
       | My first platform for programming! Simple Menus, Goto statements,
       | images. I loved making games on this thing.
       | 
       | And yes, it was highway robbery at $90+
        
         | Shared404 wrote:
         | Same here!
         | 
         | I remember hacking a loop into TI-Basic by having programs call
         | into each other, since there was no looping control flow built
         | in.
         | 
         | Never did write anything more advanced than TI-basic, I'd heard
         | horror stories of people bricking calculators, and mine was an
         | emotionally sensitive hand-me-down.
        
           | Jtsummers wrote:
           | TI-BASIC definitely had loops, though maybe not on the
           | version you had? I had the TI-85/86 (which were mostly
           | identical, the 85 was stolen by a student in the tutoring lab
           | I volunteered in in high school). Looking up TI-83 manuals,
           | they had for and while loops.
        
             | Shared404 wrote:
             | I was on a TI-83, not a plus, and couldn't find them at
             | all.
             | 
             | Always possible I was just an idiot. I remember having
             | looked it up, but I was also a dumb high schooler at the
             | time.
        
               | Jtsummers wrote:
               | What at least the 85/86 series didn't permit (86 was
               | almost identical to the 85) was direct recursion, which
               | woulds fail immediately. I don't think I ever tried
               | indirect recursion, which also would have failed. If I
               | understand correctly, the problem was that there was no
               | call stack (in the way every mainstream language does
               | things anymore). So the return address location for a
               | program was singular, if you made multiple (recursive,
               | direct or indirect) calls into a program where it would
               | return to was whatever the _last_ call set the return
               | address to. Like old school COBOL and FORTRAN where
               | procedures were non-reentrant. Of course, I was in high
               | school too and didn 't know about the inner workings of
               | computers like that. So I figured out how to use the list
               | data structure on the calculator as a stack to create my
               | own "recursive" programs either trampolining (A calls B
               | repeatedly in a loop until the list-as-stack is emptied,
               | indicating termination) or with loops (skip the call to B
               | and keep it all in one program).
               | 
               | Limitations lead to creativity.
        
               | sgtnoodle wrote:
               | Lol, unfortunately I think you just missed it. Software-
               | wise, the TI-83 was nearly identical to the plus. I
               | actually had a later revision of TI-83 that had an
               | identical housing to the plus, but with differently
               | tinted buttons.
        
               | Izkata wrote:
               | I had a TI-83+, not a TI-83, so I can't be sure but I
               | suspect you're misremembering which feature was missing:
               | The + did have while loops but didn't have functions, but
               | calling another program worked like a function call with
               | no parameters and no return value (and you could fake
               | both by using the global variables).
        
               | krallja wrote:
               | `Ans` stored the value of the last expression, so you
               | could use that as a "return value" of sorts.
        
           | paulcole wrote:
           | I wrote a fair amount of assembly for my TI-83 and some
           | assembly and C for my TI-89. I don't remember it being
           | possible to accidentally brick the calculators because if you
           | messed up enough and froze everything, you just took the
           | batteries out, opened up the case and popped out the little
           | hearing-aid battery which reset everything.
        
             | Shared404 wrote:
             | I'm sure that would work - over the years since I learned
             | much more about computers, and realized I needn't have
             | worried so much.
             | 
             | My misconception came from an article I read at some point
             | which described assembly/C (I think) programming as more
             | risky, and I just took it at face value.
        
               | paulcole wrote:
               | It was definitely annoying and if you didn't have a
               | screwdriver to get inside it was "bricked."
               | 
               | The one thing I was never brave enough to do was
               | overclock. Supposedly it was just unsoldering a capacitor
               | which would do something like 3x the clock speed.
        
         | jcalabro wrote:
         | Me too!
         | 
         | I used it to enter my school's science fair where I wrote a
         | program that was a couple thousand lines to calculate, chart,
         | and explore the relationship between musical notes and
         | frequencies. I didn't have a thesis or anything, just did a
         | bunch of programming, and the judges did not care for it haha.
         | At the time, I didn't even realize it was "programming" a
         | computer, it was just fun!
         | 
         | Once I started to learn to program for real, I thought it was
         | weird that I had to type all the characters myself rather than
         | selecting from a list of pre-defined functions!
        
       | Glawen wrote:
       | Thanks for the post, I have a ti82 with LCD screen issue, I will
       | try this technique!
        
       | dm319 wrote:
       | As an adult I've discovered the joys of RPN for calculators. I
       | use free42/plus42 on my phone which is an opensource simulator of
       | the HP42. My kids havent started using calculators yet, but I'm
       | debating whether it's a good idea to teach them RPN. I think it's
       | a better way of using calculators, but don't want them to get
       | confused in class. Add to that there isn't a simple RPN
       | calculator that I know of.
        
       | ngcc_hk wrote:
       | So many possibilities of a small key based computer.
        
         | krallja wrote:
         | CollapseOS has a "just to show it's possible" port to the
         | TI-84+ -
         | https://incoherency.co.uk/collapseos/hw/z80/ti84/index.html
        
       | Stampo00 wrote:
       | I don't know if the author will see this or not. The RF shielding
       | probably didn't get wet. It just looks like that. I have a TI-83
       | Plus Silver Edition which sports a semi-transparent case. I'm the
       | original owner. I never got a drop of liquid on it. And the RF
       | shield in mine looks exactly like yours. It has since the day I
       | bought it.
        
       | georgia_peach wrote:
       | I remember when these started taking over. Last semester's
       | calculus class became next semester's "calculator" class. Okay
       | for a few budding programmers; an educational decline for
       | everyone else. And I never understood the programming appeal.
       | Circa 1996, a thrift-store commodore was still a cheaper & better
       | programming experience.
       | 
       | I was also fairly pissed about having to pay $100+ on a
       | calculator which was wholly unnecessary for learning "area under
       | the curve" and "slope at a point". College is such a shakedown.
        
       | SnowHill9902 wrote:
       | That's an uncanny valley between an HP-32S RPN calculator or a
       | simple algebraic Casio and Octave/Matlab. I don't think TIs
       | should be needed if exams are correctly prepared by professors.
       | Good professors prepare conceptual and theoretical exams where
       | you can solve most things algebraically or even leave the end
       | result to be evaluated at a final step.
        
       | rbanffy wrote:
       | > Asking a bunch of rich suburbanite kids to spend $150-180
       | Canadian on a TI-84 Plus is one thing, but I'm not sure I could
       | really sleep at night forcing a disadvantaged family to pay that
       | much for a machine - multiple days of work at even a $15 minimum
       | wage - that surely didn't cost more than $20 to construct.
       | 
       | There's a point where you have to realize a company has a duty
       | not only to its shareholders, but to the society it exists in.
       | When you achieve a monopoly, you become responsible for a lot of
       | collaterals you normally wouldn't consider.
        
         | hinkley wrote:
         | Microsoft stumbled when they forgot that, while they had a
         | student discount for their products, the real reason so many
         | young people came into the job market with Windows experience
         | was piracy.
         | 
         | When they went after businesses for piracy, people were mostly
         | okay with that. When deep pockets are fined that does not lead
         | to moral outrage. When they made it very difficult to pirate,
         | they injured the hobbyist market.
         | 
         | There is definitely a place in the world for low margin
         | products aimed at fairness and advertising. And with hardware,
         | ignoring piracy doesn't really work, so there are really only
         | two options. Subsidized sales, or a very robust resale market.
         | The latter requires explicit support for First Sale Doctrine,
         | products designed for repair, and narrow enough gaps between
         | new and old hardware that the newest stuff is attractive but
         | not mandatory. Do some of those but not the other and you get
         | accused of paying lip service but having no solution. And for
         | the most part they are right.
         | 
         | There are YouTube videos of people buying eight broken Nintendo
         | handhelds and trying to salvage 5 working devices out of them.
         | These are noteworthy because it's harder than it should be, and
         | sometimes these people lose money on the project, only breaking
         | even from the YouTube royalties. If social justice were a goal,
         | you'd need to at least double that success rate, maybe more.
        
           | whatshisface wrote:
           | If someone is smart enough to turn eight broken Nintendo
           | handhelds into five working ones their skills would probably
           | be better put to something more useful.
        
             | hinkley wrote:
             | You can be good at more than one thing in your life. If all
             | you do is program you've hamstrung yourself badly. Some
             | people see it and course correct, others become old men,
             | full of regret.
             | 
             | I've known of two bike clubs that would refurbish old bikes
             | for kids. Once you learn enough maintenance to trust your
             | own repairs at speeds and distances most people avoid,
             | doing repairs for others isn't much of a stretch. Fixing
             | calculators or tablets or game boys wouldn't be a full time
             | job. A lot of social projects are volunteer or nonprofit.
        
             | morelisp wrote:
             | Aside from a lack of empathy this just isn't true. TV
             | repair shops aren't the great career they used to be; you
             | can't make a living on basic soldering skills, a Radio
             | Shack catalog, patience and elbow grease, and a good set of
             | screwdrivers anymore.
        
               | whatshisface wrote:
               | Most of the programmers I know would not be able to do
               | that, what I mean is that they should become programmers.
        
         | crest wrote:
         | To argue that a company's only duty is to its shareholders does
         | open one up to the argument that nobody but the shareholders
         | (and maybe the employees) owes any duty to companies (e.g.
         | respecting their property). Why should anyone pay for their
         | products or services in such a worldview? You have to be a
         | special kind of stupid to feel more sympathy for big
         | cooperations than disadvantaged pupils and their parents.
        
         | vanderZwan wrote:
         | I'm honestly surprised that groups like Pine64 haven't tried
         | making an open source competitor.
         | 
         | edit: just saw a few comments down that NumWorks is basically
         | that?
         | 
         | edit2: based on Phi and Omega[1][2] it looks like they no
         | longer truly are (probably to comply with the regulation
         | nonsense), but they still can be jailbroken.
         | 
         | [0] https://www.numworks.com/
         | 
         | [1] https://phi.getomega.dev/
         | 
         | [2] https://getomega.dev/
        
           | criddell wrote:
           | The barrier to replacing TI isn't hardware. Casio has cheaper
           | calculators and test makers generally have a pretty big
           | selection of acceptable calulators[1]. The barrier is often
           | teachers. They don't want to change from what they know
           | already.
           | 
           | 1: https://satsuite.collegeboard.org/sat/what-to-bring-
           | do/calcu...
        
       | cbanek wrote:
       | I had one of these, and I remember getting all sorts of sticky
       | soda in it. The buttons almost had a crunch to them. Still worked
       | perfectly though! I wonder where it might be after all these
       | years. That thing was a tank!
        
       | swimfar wrote:
       | A more descriptive title would be, "TI-83 LCD ribbon repair".
       | 
       | I have my old TI-86 which seems to have the same problem so I'll
       | have to try the same technique.
       | 
       | The TI calculators were amazing environments for learning
       | assembly. There are a bunch of good tutorials and the computer is
       | relatively simple and you get direct access to the display.
        
         | sgtnoodle wrote:
         | I replaced the failed ribbon cable with small wires on my
         | ti-83+ probably 7 years ago now. It was pretty straight
         | forward. I've used the calculator maybe once since then, but I
         | keep it around for nostalgia.
        
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       (page generated 2022-07-31 23:00 UTC)