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C compiler
09-15-2015, 11:45 AM
Post: #21
RE: C compiler
precisely! If I were a student, I'd probably want a TI....but I'm an engineer.....I want functionality, not exam mode. However, as I've repeated over and over again, if they were to provide it, they could prevent people from writing over any undesired areas using the MMU. They could not change that from their C code either if set up properly. Shoot, this is how Linux works...you have supervisor and user mode. If in user mode, you cannot change certain aspects of the system...only a superuser can (root).....and if you don't have that capability, you just cannot, even from a program.....so exam mode isn't an issue ONLY IF THEY SET IT UP THAT WAY. If we hack a way in, then there will be no protection. Why not embrace it and control it?

Oh well, I'm sure I'm talking to the wind anyways.

I think the solution is through an external connection....doing the intense computation on an external processor....maybe use the GPU in an X1 tegra board or something....have 300 GFlop.

Now there is an idea....a calculator with a built-in supercomputer.....building a calculator out of the X1 tegra processor (from NVIDIA). Has 2GHz quad arm core with 300GFlop GPU...that'd be a cool pocket calculator... :-)

OK, I'll get off my soapbox now :-)
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09-15-2015, 01:36 PM
Post: #22
RE: C compiler
(09-15-2015 06:50 AM)xset Wrote:  
(09-12-2015 07:19 PM)Tim Wessman Wrote:  PLEASE STAY AWAY FROM ANYTHING THAT MESSES WITH THE EXAM MODE

HP did not make adequate 50g replacement. As for me I don't care about exams. I need modern programmable device. NSpire at least has Ndless (though against TI will), but u can easily reset it rebooting device. And no global disaster happened with TI and their exam mode !

At least give us features which would compensate restrictions. I need walk on expressions (x*2+5 => {+ {* X 2} 5}), i need to draw expressions on GROB in textbook format. I need efficiently read and write files on disk: AFiles OK, but it would be too inefficient to read(write) whole list in one shot, also it would be cool to position cursor inside file. I also like to have access to programs, write program writing programs, etc. Where is programmable alert, and customizable START program ?

I am not student, its not my fault. I am working professional, why do u punish me ?

Best regards
XSet

What TW is saying is just to stay away from exam mode routines. One evil person could easily replace small comparisons and things to bypass exam mode (imagine you see a document how to bypass your atm password, even if is an isolated case gen population loses trust on that mechanism), since the firmware upload is not encripted/signed. Nothing to do with the calculator capabilities, after all the scope for the prime was already defined.

(09-15-2015 11:45 AM)webmasterpdx Wrote:  Now there is an idea....a calculator with a built-in supercomputer.....building a calculator out of the X1 tegra processor (from NVIDIA). Has 2GHz quad arm core with 300GFlop GPU...that'd be a cool pocket calculator... :-)

OK, I'll get off my soapbox now :-)

Just remote connect to a 'supercomputer' via a 40 usd android tablet Tongue

My website: erwin.ried.cl
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09-15-2015, 05:50 PM
Post: #23
RE: C compiler
(09-14-2015 04:08 PM)webmasterpdx Wrote:  Who owns the code then if not hp?

A few months back, I looked at the firmware files and saw a copyright by Inventec Besta (https://en.wikipedia.org/wiki/Inventec), though this is my own speculation, nothing more.
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09-15-2015, 06:14 PM
Post: #24
RE: C compiler
(09-14-2015 05:45 AM)cyrille de brĂ©bisson Wrote:  Hello,

> If they allowed native programming, they could use the MMU to block our code from altering any areas they want.

This is assuming that the OS does support/use the MMU, or can be modified to do so.

Cyrille

The OS does not need to be modified unless it already implements MMU protection.
If the OS does not use the MMU it's better, you can do what hpgcc3 does:
* Save all hardware registers
* Take control of the CPU exceptions, enable the MMU to create your own isolated environment
* Run the native user program in a separate address space
* Unwind the mess, shut down the MMU, restore system exception handlers
* Restore all hardware registers and return like nothing happened.

This way you could create a secure wrapper for people to run native code in a completely sandboxed environment. This could include a virtual stack where the code could take arguments from and return results (the Prime's data and code don't need to be visible from within this environment). The wrapper would be in charge of copying the arguments and results from/back to Prime memory.
Providing an environment like described above, some useful software could be written for the Prime (I'm willing to port newRPL to such environment). You could of course disallow its use during exam mode.
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09-15-2015, 06:26 PM
Post: #25
RE: C compiler
Precisely!!!
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09-15-2015, 06:27 PM
Post: #26
RE: C compiler
(09-15-2015 05:50 PM)Claudio L. Wrote:  
(09-14-2015 04:08 PM)webmasterpdx Wrote:  Who owns the code then if not hp?

A few months back, I looked at the firmware files and saw a copyright by Inventec Besta (https://en.wikipedia.org/wiki/Inventec), though this is my own speculation, nothing more.

That's interesting...
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09-18-2015, 11:35 AM
Post: #27
RE: C compiler
(09-15-2015 01:36 PM)eried Wrote:  One evil person could easily replace small comparisons and things to bypass exam mode (imagine you see a document how to bypass your atm password, even if is an isolated case gen population loses trust on that mechanism

It seems like VERY stupid idea. Why to buy expensive fancy handheld if you disable its capabilities ??? You can buy simple engineering calculator without CAS and use it during exam.

Because of that standard exams they closed architecture and don't allow to develop right software. PPL is almost OK as language, but awful as environment (development and working). We have quite good hardware locked for software development. Brrrrrr

The World is bloody imperfect, today if some company releases cool hand-held device it will necessarily make Gulag for its users. Step right, step left - execution by firing squad :-(

Best regards
XSet
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09-18-2015, 08:10 PM
Post: #28
RE: C compiler
(09-15-2015 05:50 PM)Claudio L. Wrote:  
(09-14-2015 04:08 PM)webmasterpdx Wrote:  Who owns the code then if not hp?
A few months back, I looked at the firmware files and saw a copyright by Inventec Besta (https://en.wikipedia.org/wiki/Inventec), though this is my own speculation, nothing more.
FWIW, Inventec (Inventec Multimedia & Telecom Corporation) has also been the hardware design firm for the HP 20b (aka MJ920A aka "HP Little EURO") and HP 30b financial calculators in 2008.

Greetings,

Matthias


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"Programs are poems for computers."
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09-18-2015, 09:43 PM
Post: #29
RE: C compiler
(09-12-2015 06:35 AM)webmasterpdx Wrote:  Note that it'll both support C and C++.

This could be very cool!
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09-19-2015, 03:10 AM
Post: #30
RE: C compiler
I'd like arbitrary precision integer arithmetic and to have an optimized native function to factorize (would take too long to factorize using PPPL when dealing with a 1025 digit number).
I'm doing some research on prime numbers and need that capability. I'm sure there are lots of other areas where the math needs a lot of CPU cycles....hence the desire for native programming.
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09-24-2015, 08:01 AM
Post: #31
RE: C compiler
(09-13-2015 02:06 AM)webmasterpdx Wrote:  
(09-12-2015 07:19 PM)Tim Wessman Wrote:  They aren't wince dlls, nor anything to do with wince. It is fairly common however for asian manufacturers to copy names and organization to aid with familiarity of developers internally. A lot of the OS calls are named fairly similar to windows type calls even when they have slight differences or even outright missing behavior. It can honestly get a little annoying.


Nobody at HP can help in any way with breaking open the system. We have not done anything to prevent it and hope that if/when someone does - PLEASE STAY AWAY FROM ANYTHING THAT MESSES WITH THE EXAM MODE (lights, memory, etc). If people start being able to break the exam mode things then we'll have to start screwing with stuff frequently to try and lock things down. Nobody wants that.

On wince....gotcha!

I'm not trying to break open the system. I'm trying to run C code that runs totally indepndently. The only thing the code will do is access the screen for graphics and access a preassigned matrix for input data and another for output results. HP PPL code will then transfer the results to the internal structures using existing interfaces.

I just need to know how to run C code from PPL and pass in a pointer to the input and output matrix. I've suggested that I can pass in the machine code in a third initialized matrix. Then if HP can provide a way whereby I can then run code stored in this matrix?

You provide this, you'll simply have the best math engine out there.

Exam mode would never be touched.

You do know that most customers for this product are NOT kids doing school exams....right? For that TI calculators are more accepted. This is for people that actually use math in their day to day jobs (e.g. I'm an engineer).
I wish calculator manufacturers would stop thinking that exams are the only use for calculators....

Until I get the C code capability, my preferred calculator will be Mathstudio running on android. I'd like to change that to HP Prime....but y'all won't help in that endevour...

Think about it.

Any method that can be used to run assembly or C code can be used to break the OS, and therefore screw with exam mode. I'm sure that it will be done eventually, by somebody, and the Prime will then be able to run any software the user desires, toggle the light, present an apparently "clean" calculator which can be switched on for inspection (think of the old boss key that some games had in the 80s and 90s) and so forth.

HP will then have to shift its software development focus to defeating its own user community like TI does. Does TI introduce updates for its existing calculators that fix bugs and expand features? Not at the rate HP does, because they're busy trying to keep the kids from running Super Mario Brothers and cheating on their tests. TI probably has a larger calculator division than HP and it seems that fighting the user community is taking up most of their time and to little avail.

Then again, if there comes a time that HP's calculator improvements have slowed or eventually stop, perhaps even despite existing bugs as in the cases of the 50g and the 39gii, "breaking" the OS might be in the overall interest of the user community after all.
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09-24-2015, 08:55 AM (This post was last modified: 09-24-2015 08:57 AM by xset.)
Post: #32
RE: C compiler
(09-24-2015 08:01 AM)Sukiari Wrote:  Then again, if there comes a time that HP's calculator improvements have slowed or eventually stop, perhaps even despite existing bugs as in the cases of the 50g and the 39gii, "breaking" the OS might be in the overall interest of the user community after all.

Right! Taking in account almost unusable on-board program editor, they care about damn exam mode too much :-( HP Prime is one of best handheld mini-computers, slim as smartphone with good calculator keyboard, HP is committing a crime limiting development on it. People could make it calculator of dream HP 50g + new features.
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