OpenRPNCalc

Public

Loading 3D model… large boards can take a moment.

README

OpenRPNCalc

Open-source and open-hardware scientific RPN calculator

Introduction

OpenRPNCalc is a scientific calculator based on the STM32 microcontroller. Its source code, schematics, and PCB design files are released under an open license. The goal is to develop a hardware platform with the following features:

Reproducible without special tools, using only boards produced by PCB prototyping services
A customizable keyboard to accommodate specific needs (such as RPN or algebraic logic, custom functions)
Low power consumption and long battery life
A high-quality, compact and sturdy enclosure

The hardware is inspired by the SwissMicros calculators, but is designed from scratch. The calculator features:

Reverse Polish notation with a large stack (up to 100 elements)
Double-precision arithmetic
"Standard" scientific calculator functions (trigonometric, logarithms, exponentiation, square root and power)
Error function (erf) and its inverse (erfinv), Gamma and log(Gamma) functions, combinations and permutations, p-values for Poisson, Gaussian, and chi-squared distributions
Fixed, scientific (SCI) and engineering (ENG) display modes (including SI prefixes in ENG mode), with adjustable precision from 3 to 10 digits
Calculations with uncertainties using error propagation (UNCERT mode) - a feature rarely found in software calculators and almost unheard of in hardware calculators
Formulas from relativistic kinematics (centre-of-mass two-body decay momentum, conversion between angle and pseudorapidity, beta and gamma factors)
Statistical functions: mean (or weighted mean in UNCERT mode), RMS, chi-squared of a series of values (only in UNCERT mode).
100 memory registers
Power consumption: 0.6mA running at 16MHz, 16 uA in standby mode with the LCD on, and 5 uA with the LCD off.
Optional HP48 keyboard files, with the aim to run DB48x (this is still very much WIP)

Hardware overview

Comments

OpenRPNCalc

Open-source and open-hardware scientific RPN calculator

Introduction

Reproducible without special tools, using only boards produced by PCB prototyping services

A customizable keyboard to accommodate specific needs (such as RPN or algebraic logic, custom functions)

Low power consumption and long battery life

A high-quality, compact and sturdy enclosure

The hardware is inspired by the SwissMicros calculators, but is designed from scratch. The calculator features:

Reverse Polish notation with a large stack (up to 100 elements)

Double-precision arithmetic

"Standard" scientific calculator functions (trigonometric, logarithms, exponentiation, square root and power)

Error function (erf) and its inverse (erfinv), Gamma and log(Gamma) functions, combinations and permutations, p-values for Poisson, Gaussian, and chi-squared distributions

Fixed, scientific (SCI) and engineering (ENG) display modes (including SI prefixes in ENG mode), with adjustable precision from 3 to 10 digits

Calculations with uncertainties using error propagation (UNCERT mode) - a feature rarely found in software calculators and almost unheard of in hardware calculators

Formulas from relativistic kinematics (centre-of-mass two-body decay momentum, conversion between angle and pseudorapidity, beta and gamma factors)

Statistical functions: mean (or weighted mean in UNCERT mode), RMS, chi-squared of a series of values (only in UNCERT mode).

100 memory registers

Power consumption: 0.6mA running at 16MHz, 16 uA in standby mode with the LCD on, and 5 uA with the LCD off.

Optional HP48 keyboard files, with the aim to run DB48x (this is still very much WIP)

Hardware overview

OpenRPNCalc

Share OpenRPNCalc

OpenRPNCalc

Introduction

Hardware overview

Sign in to BoardRepo

OpenRPNCalc

Introduction

Hardware overview

Repository contents

Documentation

Emulator