United States Patent 4,001,569

General Purpose Calculator having Selective Data Storage, Data Conversion and Time-Keeping Capabilities

Jan. 4, 1977
Inventors: Assignee: Hewlett-Packard Company, Palo Alto, Calif.
Filed: Apr. 8, 1975
Appl. No.: 566,144

Abstract:

A battery powered, hand-held calculator is disclosed which includes a built-in metric to U.S. conversion function for converting units from one system to the other; a degrees-minutes-seconds conversion function for converting angles or units of time from degrees-minutes-seconds to the decimal system and conversely.

10 Claims, 37 Drawing Figures


An image of first page of this patent is available (approximately 40 Kbytes). It is a TIFF class F file at 300 DPI resolution using ITU-T Group 4 Facsimile (T.6) coding.

Eric's notes:

This patent mainly describes the HP-45, although it contains detailed technical information concerning the circuitry and instruction set which is used in the entire Classic series. It contains the entire microcode ROM listing of the HP-45.
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Last updated July 17, 1995

Copyright 1995 Eric Smith

eric@brouhaha.com

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