Wikipedia / HP-42S
Wikipedia / HP-42S
The HP-42S RPN Scientific is a programmable RPN Scientific hand held calculator introduced by Hewlett-Packard in 1988. It is a popular calculator designed for science and engineering students.
Overview
Perhaps the HP-42S was to be released as a replacement for the aging HP-41 series as it is designed to be compatible with all programs written for the HP-41. Since it lacked expandability, and lacked any real I/O ability, both key features of the HP-41 series, it was marketed as an HP-15C replacement.
The 42S, however, has a much smaller form factor than the 41, and features many more built-in functions, such as a matrix editor, complex number support, an equation solver, user-defined menus, and basic graphing capabilities (the 42S can draw graphs only by programs). Additionally, it features a two-line dot matrix display, which made stack manipulation easier to understand.
Production of the 42S ended in 1995.
Specifications
Series: Pioneer
Code Name: Davinci
Introduction: 1988-10-31
Functions: Over 350
Expandability: Officially no other than IR printing (32KB memory upgrade and over-clocking hardware hacks are possible)
Features
All basic scientific functions (including hyperbolic functions)
Statistics (including curve fitting and forecasting)
Probability (including factorial, random numberss and Gamma function)
Equation solver (root finder) that can solve for any variable in an equation
Numerical integration for calculating definite integrals
Matrix operations (including a matrix editor, dot product, cross product and solver for simultaneous linear equations)
Complex numbers (including polar coordinates representation)
Vector functions
Graphic display with graphics functions and adjustable contrast
Menus with submenus and mode settings (also custom programmable) that use the bottom line of the display to label the top row of keys
Sound (piezoelectric beeper)
Base conversion, integer arithmetic and binary and logic manipulation of numbers in binary, octal, decimal and hexadecimal systems
Catalogs for reviewing and using items stored in memory
Programmability (keystroke programming with branching, loops, tests and flags)
The ability to run programs written for the HP-41C series of calculators
Programming
The HP-42S is keystroke-programmable, meaning that it can remember and later execute sequences of keystrokes to solve particular problems of interest to the user. The HP-42S uses a superset of the HP-41CX FOCAL language.
All programs are stored in one continuous program space, and may be created and edited by switching to programming mode, using the key. Subroutines are enclosed in /Label (name of subroutine) and /Return (halts execution unless it is in a subroutine in which case it returns to the caller). Keystrokes (of functions) are enclosed between and or .
In a running program, a label causes program execution to branch to the specified label and continue running at that line. Executing a GTO instruction from the keyboard moves the program pointer to the corresponding label. No program lines are executed.
is used in much the same way with one important difference: after an instruction has transferred execution to the specified label, the next RTN (return) or END instruction causes the program to branch back to the instruction that immediately follows the XEQ instruction. Programs/Subroutines can also be executed with the help label (Execute) key. The important difference between the and is that executes the label and returns to previous subroutine and continues execution from the line following ,whereas branches to the label specified and doesn't return.
packs the current subroutines and moves to new program space.nnnn can be used to reach a particular line of program.
Programming examples
A simple program to calculate area of circleProgram instructions like , , halt the program execution,which can be continued by pressing .
is used to view contents of a register,For example R in the above example.
Using Integral and Equation Solver
It is necessary to write a program or subroutine that evaluates f(x) for the function which needs to be solved or integrated. Variables used in program should be declared using
Here is a sample program to solve the equation °F = (9/5×°C) + 32After, accessing the solver using ( ), select program .
In a similar way, expressions can be integrated. After selecting the variable of integration, enter the lower limit and then press on , similarly input (upper limit) and (accuracy).
Emulators
HP 42s can be accessed through Android Emulators like Emu42 and Free42.
Reference Books
Guides and Collections of Keystroke Programs
Documentation for the HP 42S calculator at hpcalc.org
HP-42S Owner's Manual
HP-42S Programming Examples & Techniques
Step-by-Step Solutions: Electrical Engineering (42S)
Step-by-Step Solutions: Mechanical Engineering (42S)
Advanced Circuit Analysis with the HP-42S
An Easy Course in Using the HP-42S
Educational Texts on RPN calculators
Algorithms for RPN Calculators
Scientific Analysis on the Pocket Calculator
Engineering Statistics with a Programmable Calculator
Applied Mathematical Physics with Programmable Pocket Calculators
Mathematical Astronomy with a Pocket Calculator
Handbook of Electronic Design and Analysis Procedures using Programmable Calculators
Calculator Programs for Chemical Engineers(Vol 1 & 2)
Collection of Algorithms/Keystroke Programs for HP 41/HP 42S
Software Library for HP 41 Programs(Compatible with HP 42S)
See also
References
Further reading
HP-42S Quick Reference Guide (1 ed.). Corvallis, OR, USA, Dex Smith. October 1988. 00042-92222E.
External links
HP-42S resources on hp42s.com (defunct as of July 2017)