CASIO fx-4000P scientific calculator from 1986

[badaze]

In my opinion it is far better than the 602P it replaced. Fortunately the 4000P is affordable (unlike the 602P) and easy to find. I bought several for a few € at flea markets even boxed.
It is rare to get a non working one - the last I bought at a charity store - but its weakness resides in the front bezel that often detach.

PS : I’m really interested in the 2 KB trick.