What it does
Free42 independently implements the HP-42S calculator experience and provides binary and decimal floating-point builds.
Free42 reimplements the HP-42S and its printer without requiring an HP ROM. It retains that programmable calculator workflow and adds program exchange, clipboard operations and saved states. Program text pasted in PRGM mode is appended, while unrecognised instructions are silently ignored, so compare the imported listing. A .raw file carries programs; a .f42 state includes variables, stack, flags and solver/integrator state, and loading it replaces the active state. Desktop packages include Binary and Decimal builds; mobile distribution is Decimal only. Decimal provides 34 decimal digits, while Binary has nearly 16 and cannot represent values such as 0.1 exactly. The provider recommends Decimal for full legacy-program compatibility. GPLv2 builds cover Windows, Mac, Linux, Android and iOS; Plus42's algebraic expressions, attached units and plotting are a separate product.
Strengths
- HP-42S-style calculation environment
- Binary and decimal floating-point builds
Best for
- Continuing an HP-42S-based calculation workflow