42S with nonvolatile RAM

Long time no see.

I just made modifications of an HP 42S to make its memory nonvolatile by using an F-RAM. It seems successful so far.

Double speed HP 42S with nonvolatile RAM



You are a 42S master modder. ;-)


No words.....................thank-you for sharing your great work!


I am envious. Not of the calc, but of your knowledge and abilities. Thanks for the inspiration.


Dear Lyuka,

you cannot imagine how many times I have visited your web,

your mods are so well documented.

I am curious, how many 42s's do you have???



Thank you for your compliments.

Actually I have two defective 42S (and two other flawless one, of course ;-)

I really think 42S useful, and for they were defective, I had no hesitation to modify them.


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