Utilities Windows
Free42 for Windows
Run HP-42S calculator programs and perform scientific calculations on Windows with Free42, a free, open-source calculator simulator that needs no ROM image.
- Operating system
- Windows Vista or later, according to the publisher
- Architecture
- Main package not explicitly labeled; separate 32-bit package available
- Download package
- ZIP archive containing Binary and Decimal editions
The linked file is the publisher's main Windows package, not its separately linked 32-bit package. A Visual C++ Redistributable may be required.
Link checked · Download guidance
What is Free42?
Free42 recreates the HP-42S scientific programmable calculator and HP-82240 printer in software. Use it for scientific calculations, complex numbers, matrices or existing HP-42S programs without supplying a calculator ROM image. The Windows download includes both Decimal and Binary editions of the same application.
Choose Decimal when compatibility with HP-42S programs matters: the publisher documents 34 decimal digits of precision. Binary uses nearly 16 decimal digits and can be faster, but its representation of decimal fractions can cause some calculator programs to fail. These are numerical-engine choices, not separate products.
Free42 can exchange programs through files or clipboard text, copy matrices in a spreadsheet-compatible tab-delimited format, and save calculator states containing programs, variables and settings. Importing a state replaces the active state; it is not the same operation as adding a program. The Windows package requires Vista or later, and the publisher notes that a Visual C++ Redistributable may also be needed.
What it offers
- Run programs written for the HP-42S without an HP-42S ROM image.
- Perform scientific calculations with complex numbers and matrices.
- Choose between Decimal and Binary numerical engines, both included in the desktop download.
- Import and export programs, or copy and paste program listings and spreadsheet-compatible matrices.
- Save and switch calculator states containing programs, variables, stack contents and settings.
Good to know
- Binary floating-point cannot represent some decimal fractions exactly and can cause certain HP-42S programs to fail; use Decimal when that compatibility is required.
- Importing a calculator state replaces the previously loaded state; only one state can be active at a time.
- Windows may require an additional Visual C++ Redistributable; Windows versions before 10 need older redistributable versions.
Product images
Sources
References used for this listing. Retrieval dates do not indicate hands-on testing.
- Free42 - Download ↗Retrieved
- Free42 : An HP-42S Calculator Simulator ↗Retrieved
- Free42 History ↗Retrieved
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