free42
An HP-42S Calculator Simulator (binary version)
Free42 is a re-implementation of the HP-42S Scientific Programmable Calculator
and HP-82240 Printer.
It is a complete rewrite, not using any HP code. It does not require an HP-42S
ROM image.
Free42 Binary (free42bin) uses the PC's FPU; it represents numbers as IEEE-754
compatible double precision binary floating point, which consumes 8 bytes per
number, and gives an effective precision of nearly 16 decimal digits, with
exponents ranging from -308 to +308.
https://thomasokken.com/free42/
Utility