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accuracy of integration and solve routines HP 15C LE
Message #1 Posted by Jan on 2 Feb 2012, 5:34 a.m.

Hi,

Has anybody tested the integration- and/or solve-function of the 15C LE? And if so, do they seem work properly or not? Doing a lot of algebraic work I primarely use my calculators for checking results. With an increase in speed of 100 times the speed of the original 15C (of which I got 2) and therefore even exceeding the speed of my 32SII and 48G, the 15C LE seems a perfect tool for the job. That is, when I can rely on it. Thanks for your respons.

      
Re: accuracy of integration and solve routines HP 15C LE
Message #2 Posted by Marcus von Cube, Germany on 2 Feb 2012, 8:40 a.m.,
in response to message #1 by Jan

The accuracy of the 15C LE is exactly the same as that of the original 15C because it runs the same software. All problems are related to the operation environment of the emulation (display, battery, keyboard).

            
Re: accuracy of integration and solve routines HP 15C LE
Message #3 Posted by Jan on 2 Feb 2012, 12:51 p.m.,
in response to message #2 by Marcus von Cube, Germany

Thanks for the info. I had the idea though that the original firmware had to be reverse-engineered since the original documentation was lost at HP. Or is that just a rumour? If not, was the reverse-engineering done in an appropriate way?

                  
Re: accuracy of integration and solve routines HP 15C LE
Message #4 Posted by Marcus von Cube, Germany on 2 Feb 2012, 1:03 p.m.,
in response to message #3 by Jan

I'm not the most qualified to answer your question but I doubt that any reverse engineering was really necessary. The original code is run in a virtual environment as if the nut processor were still there. It's not, the instructions are interpreted by some software running on the ARM chip. This piece of software not only has to implement the processor but all of the peripherals, too, and map them to the real hardware. Here the trouble has its origins.

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