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Calculator hackers crack OS signing key, opening a closed platform

ticalc.org

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Re: Calculator hackers crack OS signing key, opening a closed platform

#31

Post by [deleted] »

euroclydon wrote: post #28
icefox wrote: post #25

Earlier quoted context omitted.

Crazy what they have these days. Back when I was in high school (first year they required the 83) our teachers simply required we showed every step. So we could get the answer with a few key presses, but unless we showed how to get the answer we wouldn't get credit. Of course I wrote programs to solve the problems step by step and print out the answer, but I guess the system works because in the process of being clev…

I had a nice and crazy little Chinese professor for numbers theory in college. I never knew what he was saying, but he would tell us the questions for the exam the day before. I asked him if I could use my ti-92+ and he said yes, so I just programmed in brute force algorithms, entered in the data, then sat back while the 10MHz processor crunched.

[deleted]

Re: Calculator hackers crack OS signing key, opening a closed platform

#32

Post by tsuraan »

mahmud wrote: post #2

A man has just become immortal. TI scene will never be the same again; the TI-83 calculator turns to an open platform today (The 83 is mandatory in U.S. education and sometimes distributed for free, all American High Schoolers use it, and did so for at least the last 10 years.) Bonafide 3rd party OSes can be loaded on it now, no more shells. Help crack the rest of the keys (Win32 and Linux clients; linux version requ…

Do you have any refs for the TI83 being mandatory in US high schools? A quick google search puts your post at the top and nothing too relevant anywhere else. I graduated from a public HS less than ten years ago, and I used the far superior HP-48G throughout the entire thing :) I never took math classes from my HS, but I do remember my friends who were taking HS courses having an assortment of TI81 - TI89 calcs.

Re: Calculator hackers crack OS signing key, opening a closed platform

#33

Post by skolor »

rflrob wrote: post #18
jacobolus wrote: post #7

Earlier quoted context omitted.

> (The 83 is mandatory in U.S. education and sometimes distributed for free, all American High Schoolers use it, and did so for at least the last 10 years.) It's a bit off the subject, but this has always struck me as a terrible scam. For the material it is used for (introductory calculus) and the way it is used, one of these TI calculators hurts student learning and understanding more than it helps, and there is no…

>(Personally, I made it through high school and then up through upper-level undergraduate mathematics, physics, econometrics, etc. courses without ever buying a graphing calculator, so it’s clearly not strictly mandatory for current curricula, but students and parents get the impression that it is essential, and the vast majority of students do buy them, so the effect is about the same.) It's actually much harder to…

I'm not so sure about this. In high school, I spent the first two years doing everything using a TI-83+ (Algebra II and Pre-Calc). However, when my TI-83 stopped working (and got a TI-89), I stopped using a calculator almost all together. For both years of Calculus, I did all the work by hand, turning to the calculator only at the end when I needed a final result (and usually tried to do that in my head/with pen and paper anyway).

I would say the that helped me immensely with understanding not only understanding the material, but being able to work it out faster. I'm now able to roughly estimate (within a decimal point or two) most basic math problems in only slightly longer than it does for most students to do it on a calculator. In fact, I tend to work problems out significantly faster than most students who simply punch everything into a calculator and get the results from there, if only because I understand the problem better from working it out by hand and know better how to approach it. Being able to estimate square roots in my head has been vastly beneficial, and would be a skill well worth knowing.

Re: Calculator hackers crack OS signing key, opening a closed platform

#34

Post by duskwuff »

dan_the_welder wrote: post #11
jacobolus wrote: post #7

Earlier quoted context omitted.

> (The 83 is mandatory in U.S. education and sometimes distributed for free, all American High Schoolers use it, and did so for at least the last 10 years.) It's a bit off the subject, but this has always struck me as a terrible scam. For the material it is used for (introductory calculus) and the way it is used, one of these TI calculators hurts student learning and understanding more than it helps, and there is no…

And now a cracked OS allows cheating since they have an approved 'test mode" to prevent access to stored files. http://education.ti.com/educationportal/sites/US/homePage/ns... So blinking the led without any access blocking will be an early task for the subversive TI hacker.

Or, at least, it would if anyone used the Nspire. I've never heard of a school using them - everyone has standardized on the 83 / 84.

Re: Calculator hackers crack OS signing key, opening a closed platform

#35

Post by charlesju »

jacobolus wrote: post #7
mahmud wrote: post #2

A man has just become immortal. TI scene will never be the same again; the TI-83 calculator turns to an open platform today (The 83 is mandatory in U.S. education and sometimes distributed for free, all American High Schoolers use it, and did so for at least the last 10 years.) Bonafide 3rd party OSes can be loaded on it now, no more shells. Help crack the rest of the keys (Win32 and Linux clients; linux version requ…

> (The 83 is mandatory in U.S. education and sometimes distributed for free, all American High Schoolers use it, and did so for at least the last 10 years.) It's a bit off the subject, but this has always struck me as a terrible scam. For the material it is used for (introductory calculus) and the way it is used, one of these TI calculators hurts student learning and understanding more than it helps, and there is no…

I have the exact opposite reaction to graphing calculators. I used them to ace my SAT IIs back in the day simply because I understood all the functions of my calculator than every other non-hacker in the room. I even used to program small BASIC games on it when I was bored in class. There still isn't a good device to program on that is inconspicuous in the classroom.

Re: Calculator hackers crack OS signing key, opening a closed platform

#36

Post by eslifka »

tsuraan wrote: post #32
mahmud wrote: post #2

A man has just become immortal. TI scene will never be the same again; the TI-83 calculator turns to an open platform today (The 83 is mandatory in U.S. education and sometimes distributed for free, all American High Schoolers use it, and did so for at least the last 10 years.) Bonafide 3rd party OSes can be loaded on it now, no more shells. Help crack the rest of the keys (Win32 and Linux clients; linux version requ…

Do you have any refs for the TI83 being mandatory in US high schools? A quick google search puts your post at the top and nothing too relevant anywhere else. I graduated from a public HS less than ten years ago, and I used the far superior HP-48G throughout the entire thing :) I never took math classes from my HS, but I do remember my friends who were taking HS courses having an assortment of TI81 - TI89 calcs.

I don't have any references for you, but my middle school and highschool required graphing calculators. And they very strongly pushed the ti-83+, claiming that students would be horribly lost if they couldn't follow along with the teacher's instructions. In reality the teachers were all incompetent with the calculators and the school wanted everyone to have an 83+ because that was the only platform on which the teachers knew the process for erasing the memory.

Re: Calculator hackers crack OS signing key, opening a closed platform

#37

Post by xcombinator »

hehe, I remember trying to convince my teacher for letting me use the nintendo DS on exams. You have to try, it's funny to see their faces.

Now you can use: 1.Nintendo DS. You can make or port(from linux) whatever you want in c, import Lapack libraries, use eigenmath homebrew for everything else. 2.Iphone.Good support for c too. 3. netbooks...

Re: Calculator hackers crack OS signing key, opening a closed platform

#38

Post by _phred »

eslifka wrote: post #36
tsuraan wrote: post #32

Earlier quoted context omitted.

Do you have any refs for the TI83 being mandatory in US high schools? A quick google search puts your post at the top and nothing too relevant anywhere else. I graduated from a public HS less than ten years ago, and I used the far superior HP-48G throughout the entire thing :) I never took math classes from my HS, but I do remember my friends who were taking HS courses having an assortment of TI81 - TI89 calcs.

I don't have any references for you, but my middle school and highschool required graphing calculators. And they very strongly pushed the ti-83+, claiming that students would be horribly lost if they couldn't follow along with the teacher's instructions. In reality the teachers were all incompetent with the calculators and the school wanted everyone to have an 83+ because that was the only platform on which the teach…

I can correlate the "strongly recommended TI part," having graduated HS in 2001. I used an HP-48GX and yes, at times, it was hard to adapt the teacher's instructions. My friend and I both had 48's, and we helped each other work it out. When we got into symbolic manipulation, statistics, and inspecting 3D graphs, the HP left the basic TI models in the dust.

But yeah, no problem using a HP graphing calculator when I was in high school; took trigonometry, AP calculus, AP physics, and the SAT all using that calculator. Even had a full year's trig notes stashed in there, though I honestly didn't use them on any exams; just handy for calculus homework.

Re: Calculator hackers crack OS signing key, opening a closed platform

#39

Post by jsonscripter »

blasdel wrote: post #5
Eliezer wrote: post #3

Earlier quoted context omitted.

Holy Cthulhu, you can crack 512-bit RSA in 73 days on a single computer these days?

On a single ridiculously slow computer. Even the slowest Core 2 Quad would be able to factor 8x faster.

Could you do this for the ipod nano, 2nd generation? I've been wanting to get RockBox on it for years, but the firmware is encrypted!
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