Hewlett-Packard 9100A
Illustration — "The new Hewlett-Packard 9100A personal computer" is "ready, willing, and able.. To relieve you of waiting to get on the big computer." The Hewlett-Packard 9100A (HP 9100A) is an early programmable calculator (or computer), first appearing in 1968. HP called it a desktop calculator because, as Bill Hewlett said, "If we had called it a computer, it would have been rejected by our customers' computer gurus because it didn't look like an IBM. We therefore decided to call it a calculator, and all such nonsense disappeared." An ad for the 9100A in 1968 Science magazine contains one of the earliest documented use (as of 2000) of the phrase personal computer.
Also recorded as HP-9100A · HP 9100A · HP 9100
Hewlett-Packard 9100A

Swtpc6800 en:User:Swtpc6800 Michael Holley · Public domain
- Field
- programmable calculator
- Period
- 1968
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Illustration — "The new Hewlett-Packard 9100A personal computer" is "ready, willing, and able.. To relieve you of waiting to get on the big computer." The Hewlett-Packard 9100A (HP 9100A) is an early programmable calculator (or computer), first appearing in 1968. HP called it a desktop calculator because, as Bill Hewlett said, "If we had called it a computer, it would have been rejected by our customers' computer gurus because it didn't look like an IBM. We therefore decided to call it a calculator, and all such nonsense disappeared." An ad for the 9100A in 1968 Science magazine contains one of the earliest documented use (as of 2000) of the phrase personal computer.
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History
• Illustration — Electronic calculator prototype, made by Thomas E. Osborne for Hewlett-Packard, 1964, in the National Museum of American History The device descended from a prototype designed by engineer Thomas "Tom" E. Osborne, who joined the company when HP adopted his idea. An engineering triumph, the logic circuit was produced without any integrated circuits. The CPU was entirely executed using discrete components. With CRT readout, magnetic card storage, and printer, the price was around. Thanks to its high speed operation an order of magnitude faster than competitors – addition or subtraction took just 2 ms, multiplication 22 ms and division 27 ms – the device could quickly execute not just regular trigonometric functions (330 ms) or logarithms (130 ms) but many iterative computations when following a program. This made the 9100A the first scientific calculator by the modern definition, and also marked the beginning of Hewlett-Packard's long history of using Reverse Polish notation (RPN) entry on their calculators. Due to the similarities of their machines, Hewlett-Packard was ordered to pay about in royalties to Olivetti after copying some of the features adopted from the Programma 101, like the magnetic card and the architecture.
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Notes from the source article
These works are cited by the source article, in its own numbering. They are recorded as its citations, not as sources VALÉORINE has verified.
- 1.Aaron, Clark. Wired 8.12: Must Read: The First PC. Dec 2000.
- 2.Note in: WANTED - Data Acquisition Corp. DAC-512. www.oldcalculatormuseum.com. Note with asterisk at the end.
- 3.Hewlett-Packard. History of the 9100A desktop calculator, 1968.
- 4.HP9825.com. Osborne's Story.
- 5."How the Model 9100A Was Developed", Bernard M. Oliver, September 1968, Hewlett-Packard Journal]
- 6.1994 letter from Tom Osborne to Barney Oliver, hp9825.com
- 7.Monoskop/Whole Earth. 9100A Calculator. Whole Earth Catalog (fall 1968), no. #1010. 34. 1968.
- 8.The 9100 Part 2. www.hp9825.com.
- 9.HP9100. hpmemoryproject.org.
- 10.Old Computers. Olivetti Programma P101/P102.
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