ARM HP-12C devkit and cable?

[Jeff O.]

For the sake of the following discussion, I will refer to the current 12C platform which emulates the original 12C rom on an ARM-based platform as the 12C+. To the best of my knowledge, this hardware is identical to the 15C LE hardware.

(08-05-2014 02:26 PM)Thomas Radtke Wrote:  My hope was somehow to more or less replace the 12C firmware by that of the 15C and upload it to the 15C LE. Maybe it wouldn't be as trivial as that anyway.

I’m not sure if I understand your hope. Did you hope to somehow cut the 15C rom portion out of the 15C LE firmware, cut the 12C rom portion out of the 12C+ firmware, then insert the 15C rom into the hole in the 12C+ firmware so that its emulation layer would then run the 15C code? That sounds like an interesting idea. If one had access to the actual firmware files, one could inspect them with a HEX editor, but I don’t see how it would be possible to tell where the emulation code stopped and the original rom code started in either file. But then again, I don’t know much about such things (as is probably quite obvious to those who do), so maybe it would be possible.

Still, it sounds like our best bet for a bug-free implementation of the 15C functionality on 12C+/15C LE platform would be for a clever person to wrap the original 15C rom code in a newly developed emulation layer to run on the 12C+ and 15C LE platform. I'm sure that clever person could most probably provide functioning brownout detection while her or she was at it. Unfortunately, such a clever person would run the risk of making HP's lawyers angry, so it is probably not a reasonable thing to ask someone to do. (I believe Forum member “uhmgawa” pursued getting HP’s permission to use the original code in such a manner, but could not get past their legal ramparts.) As an alternative, a clever person or a clever team of people could almost certainly develop firmware for the 12C+/15C LE platform which would simulate the 15C in all respects (and provide some functioning brownout detection, of course, plus any appropriate augmentations to the original capabilities) without actually using any code owned by HP. That would of course be a lot of work and again may be a lot to ask.