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R47: A Beginner’s Journey
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R47: A Beginner’s Journey

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R47 front panel

Motivation

The closest approaches toward a comprehensive first-party user manual for the C47/R47 are:

Because the C47 forked from the WP43 project, their manuals are of some use, provided you are willing to mentally translate the considerable genetic drift that has occurred since that fateful point.

The incompleteness of all this has driven me to document my own journey toward enlightenment with the R47.1

Reference Tables

What the C47/R47 project has in lieu of a user manual is a huge list of loosely connected PDFs generated from a single master Excel spreadsheet, which is not itself published. The entry points least likely to leave you lost within that maze are:

An Outsider’s Humble Offerings

That brings me to my own writings on this topic, largely meant to fill gaps left by the above:

  1. A Beginner’s Journey — you are here!
  2. Unboxing — a vignette
  3. R47 vs DM32 — a comparative review
  4. Basic User Functionality
    • Setup — with a focus on the most important configuration choices to be made early on
    • Number Display Modes — the settings most likely to change continuously with use
    • Data Types — it may seem low-level, but it is fundamental to the way the R47 operates
    • Swaps — there is more to it in the R47 than x⇋y
    • Trigonometry — by these sines and cosines wilt thou know the quality of thine calculator
    • The Catalog — arguably your last resort
  5. Programming
  6. Application-Specific Modes
  7. Hardware
    • Determining Battery Health — imagine a calculator powerful enough to diagnose its own power source…
    • USB-C — marvel at what all one can do by plugging this battery-powered machine in
  8. Glossary

You can find all of the above via Fossil’s flat alphabetical list, but that is more useful for browsing the non-R47 material in this wiki.

Me & My Limited Goals

I am a complete outsider to the C47/R47 project,2 having taken a roundabout path to get here in time for the denouement.

I tell you this so that you understand where these wiki articles — or blog posts, if you prefer — are coming from. I have long experience with HP calculators, RPN and non, but I am not anyone’s idea of an insider or expert. I am an end user, a low-grade enthusiast, and an idiosyncratic collector. Some will find this perspective useful, others amusing, and still others annoyingly ignorant. Sorry; how it is.

I have no wish to produce a third-party R47 user manual, neither by displacing the efforts ongoing within the C47 project, nor by joining the C47 project as a technical writer. The prior paragraph should answer the “why” of that adequately; do you really want a relative ignoramus like me writing your calculator manual? Didn’t think so. The best I can hope for is to approximate the state of “beginner’s mind” wisely praised by the Zen Buddhists, bringing a fresh perspective to this project. Failing that, I can at least hope that my self-appointed gadfly role will spur the C47 project’s internal efforts along.

In the meantime, I will continue as you see above, making an ad hoc exploration, with directions taken as needs arise and inspiration strikes.

Numbers in Prose

Inline calculator numbers in this work are presented in a format mimicking that of a bare-bones scientific calculator made for the US market: . for the radix separator and naught else: no “thousands“ commas and no space-grouped decimals.

While this solves practical problems I run into as a writer,3 it is not meant to imply a suggested configuration, suited to use on an actual calculator. The predefined locales are far better starting points.

In the rare instances where I include an R47 screenshot, I use DFLT mode, usually from a freshly RESET state besides.

License

This work is © 2025-2026 by Warren Young and is licensed under CC BY-NC-SA 4.0

  1. ^ As a come-lately end user who never owned a DM42 [n], who further has zero expectation of ever buying one with the intent of converting it to a C47, I use the production name R47 almost exclusively on this site, being the device I actually have here at hand.
  2. ^ My sole connection to the C47 project’s complicated history is that I once built a WP34s, which has largely been gathering dust ever since. I could spend pages on the reasons for that, implicitly explaining why I do not believe my R47 will become another shelf queen in my local collection, but I can distill it to this simple observation: the R47 has a vastly superior user interface, both hardware and software. Thus why I pressed the Buy button despite knowing that the R47 evolved from the WP34s.
  3. ^ English also uses commas, dots, and spaces as separators, which leads to different pressures when sprinkling example numbers into prose than when calculating with those numbers on-device. In my minimalist scheme, the decimal dot is easy to discern from a sentence-ending period in most fixed-width fonts by being much bolder. I further eschew the comma as a thousands separator, and I do not create confusions with word-separating spaces by using it to group decimals.