Nonpareil – microcode-level simulator for electronic calculators

Nonpareil is a simulator for classic Hewlett-Packard calculators introduced during the 1970s and early 1980s. Rather than simply reproducing their mathematical functions, it runs the original calculator microcode to provide a much more faithful simulation.

Using the original microcode means calculations follow the same internal algorithms as the physical devices, including their binary-coded decimal (BCD) arithmetic. Nonpareil also attempts to match the original microinstruction execution rates, although timing can be affected by the host computer.

The software supports an extensive collection of HP calculators, including the Classic, Woodstock, Spice, Nut and Voyager families. These range from early scientific and business calculators to programmable models such as the HP-41CX and HP-16C.

Nonpareil provides a GTK graphical interface that reproduces the appearance and operation of supported calculators. It also offers experimental emulation of the HP 82143A printer. The application still uses GTK2 and several older dependencies, which may complicate installation on modern Linux distributions.

This is free and open source software.

Key Features

• Simulate classic Hewlett-Packard calculators using their original microcode and arithmetic algorithms.
• Supports HP-35, HP-45, HP-55 and HP-80 models from the Classic family.
• Emulates HP-21, HP-22, HP-25 and HP-27 calculators from the Woodstock family.
• Supports HP-31E, HP-33C, HP-34C, HP-37E, HP-38E and HP-38C models from the Spice family.
• Emulates the HP-41CV and HP-41CX programmable calculators.
• Supports HP-11C, HP-12C, HP-15C and HP-16C Voyager calculators, together with a modified HP-15X model.
• Attempts to reproduce the original microinstruction execution rates.
• Provides experimental HP 82143A printer emulation, with output that can be saved as a PNG image.

Website: github.com/brouhaha/nonpareil
Support:
Developer: Eric Smith
License: GNU General Public License v2.0

Nonpareil is written in C. Learn C with our recommended free books and free tutorials.

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