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Joined: Jun 2005
> but is it possible?
Possible? Yes.
Easy? No.
There are two approaches. One is to remove the chip, decapsulate the die using fuming nitric acid (sometimes mixed with sulphuric acid). Then a photomicrograph is taken, and the ROM bits should be visible. These chips are old enough that they aren't likely to have metal layers above the ROM. This is the method Peter Monta used to get the HP-35 ROM dump, except that the chip was in a metal can so he only had to saw the lid off rather than dealing with acids.
The other approach is to figure out how to get the part into a test mode in which the internal Saturn bus activity is visible on the package pins, then run the self-test, can capture the ROM data as it is checksummed. This is what I've done on the Spice and Voyager calculators, although with most of them the bus is always available. I have some but not all of the information necessary to do this to the 32SII.
However, if I were to extract the 32SII ROM by either method, I would still be unable to provide a copy of it to anyone. Unlike the Voyager and earlier calculators, HP did copyright the firmware of the Pioneer and Clamshell calculators.