[LEARAX]

While I agree with your sentiment, a big part of why the TI-84 is so ubiquitous is because they're required for standardized tests. I suppose their reasoning is that supporting assembly programs makes it trivial to break/fake the test mode on their calculators.

That said, they didn't even use test mode when I took the SAT, so I don't know.

[jcfields]

It's been a while since I've taken the ACT or SAT, but it seems unnecessary to me to allow graphing calculators at all. I'm pretty sure you can get through any 4-year engineering program without ever using more than a good scientific calculator on an exam (and that's all you're allowed to use on the FE/PE exams), so it ought to be more than sufficient for high school algebra or trig.

I would actually take it a step further and say that graphing calculators aren't even that useful in instruction, especially now that students all have computers and can run Desmos, MatLab, or whatever. I had a TI-86 in high school, and the only class in which I found it indispensable was A.P. Statistics. Maybe I'm being narrow-minded, but I always thought those things were a bit silly and gimmicky and sort of resented that my parents had to buy me one for school.

[G4E]

I don't know if it is common, but that's exactly what my engineering school did : no graphical calculator allowed through all the cursus. They would provide a "basic+ calculator" (a basic calculator with square, square root, and some "advanced" math but not a lot) to each test and you'll have to deal with that.

I hated it while in school, but retrospectively i think it was a pretty good idea actually :)

[Polylactic_acid]

It seems like calculators exist for the features they don't support more than the features they do support.

[souprock]

The proper fix is to store user data and run user code only when removable media is inserted. The calculator could hardware-disable flash writes when removable media is detected, and then do a full reset when removable media is removed.

Ideally it would be an SD-card plugged in at the top edge of the calculator. The area around that connector could be clear plastic, with visible circuit traces running to the CPU.

[lozaning]

If they came out with something like this I bet someone would just start selling modchips.

[souprock]

It'd be less likely than with the currently selling calculators. Are we seeing modchips now? I don't think so.

Of course it is always possible to fully replicate the calculator. I'm sure there is a Chinese factory that could do it. Stopping a trademark violation like that is the job of the port inspection and customs enforcement people. The situation becomes like illegal drugs, but with much lower demand and much more difficult production.

Simply replacing the chip is some serious electronics work. These aren't socketed DIP chips. They aren't even BGA. TI puts the bare naked silicon chip right on the board, bonds wires from it to the board, and then covers it with a blob of black glue.

My suggestion of clear plastic makes this even harder. Modifications would need to look normal. The part of the board between the SD card socket and the CPU should have a minimum of clutter and a colorful boarder box, making it easy to see where one should look for modifications.

[abakker]

I still remember before test mode, when the teacher would just come around and do 2nd, +, 7,1,2 and that would reset the calc to factory settings. It became mandatory to have the USB adaptor to reload apps.

The Ti83 is how I learned to program.

[tyingq]

Interesting...is that roughly uncapturable by an application, sort of like ctrl-alt-del in windows?

[e2e8]

No, you could simply write a program that you ran ahead of time that would simulate the correct screens in response to their inputs and make it look like the calculator was reset when in fact it was not.

[appleflaxen]

This is trivial to solve: the testing centers can purchase and maintain whatever model of calculator they wish to.

[siraben]

The TI-84+ doesn't even have a test mode. You can have data that survives a RAM clear by grouping and ungrouping the data.

[devenblake]

IIRC holding the left and right buttons and pressing the power(?) button did put it in a special test mode.

[cjsawyer]

For my engineering college tests I wasn’t allowed to use my TI84, I had to use a non programmable model.