HP-42S
Programmable RPN Scientific hand held calculator by Hewlett Packard.
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
64 KB of ROM
8 KB of RAM
Functions: Over 350
Expandability: Officially no other than IR printing (32 KB memory upgrade and over-clocking hardware hacks are possible)
Peripherals: HP 82240A infrared printer
Features
All basic scientific functions (including hyperbolic functions)
Statistics (including curve fitting and forecasting)
Probability (including factorial, random numbers 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
Named variables, registers and binary flags
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 PRGM key.
The public source identifies “HP-42S” as programmable RPN Scientific hand held calculator by Hewlett Packard. This brief keeps that definition visible, then builds a research path around HP-42S, Programmable and Scientific.
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