Utilities macOS
Free42 for macOS
Use an HP-42S-style programmable scientific calculator on Mac, run HP-42S programs and exchange calculations through the clipboard with free, open-source Free42.
What is Free42?
Free42 brings the HP-42S scientific programmable calculator and HP-82240 printer simulation to macOS. It is a complete reimplementation rather than a ROM-based emulator, so an HP-42S ROM image is not required. Its RPN calculator interface suits people who want to continue using HP-42S programs and workflows on a desktop computer.
The Mac download includes both Decimal and Binary versions. Decimal provides 34 decimal digits of precision and is the publisher's recommendation when full HP-42S compatibility matters. Binary uses nearly 16 decimal digits of precision and can be faster, but it cannot represent fractions such as 0.1 exactly; that difference can break some existing programs.
Free42 can load and save programs, copy and paste numbers, matrices and program listings, and save calculator states containing programs, variables and settings. State files replace the active calculator state, unlike program files that add programs to it. The publisher specifies macOS 10.15 Catalina or later for this ZIP package.
What it offers
- HP-42S-compatible calculator interface and program support without an HP ROM image.
- HP-82240 printer simulation alongside the scientific programmable calculator.
- Decimal and Binary calculation versions included in the Mac download.
- Clipboard exchange for real and complex numbers, matrices and program listings.
- Import and export programs, or save and switch complete calculator states.
Good to know
- Binary floating-point cannot represent some decimal fractions exactly and can cause certain HP-42S programs to fail; use Decimal when compatibility is required.
- Requires macOS 10.15 Catalina or later.
- Pasting a program silently ignores text that is not recognized as HP-42S instructions; the publisher recommends checking the imported listing.
Product images
Sources
References used for this listing. Retrieval dates do not indicate hands-on testing.
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