Uploaded December 2021 | Updated September 2026, 2 weeks ago

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The HP 48 calculator is programmed using Reverse Polish Lisp, RPL, however, the RPL available to the end user, is actually a small subset of a larger, richer, RPL language, which the HP 48 calculator’s operating system is actually written in. To distinguish between these two versions of RPL, the standard user accessible RPL is called User RPL and the richer superset is called System RPL, or SysRPL.

A simple User RPL program to sum the squares from 1 to n is shown alongside an equivalent System RPL version. The performance of the programs is then compared for the sum of squares from 1 to 2000.

Jazz System RPL and machine language development environment for the HP 48: hpcalc.org/details/1670

Introduction to System RPL and Assembly Language by James Donnelly: hpcalc.org/details/7114

Faulhaber's formula: en.wikipedia.org/wiki/Faulhaber%27s_formula

- Contents -
0:00 Intro
1:10 User RPL and System RPL programs
3:28 Test programs and compare performance
4:21 Program completion comparison
4:29 Closing