The historical role of the Programma 101
As usual, determining a calculator's importance in history is a largely subjective matter. Every machine will have its fans, claiming for their beloved machine all the possible titles or records.
The first personal computer?
In my opinion, the Programma 101 is a programmable calculator, not a computer. The difference might be sometimes subtle, but the high-level machine operations are quite typical of a calculator, not of a computer. The miminum data entity that the P101 can handle is a signed, 11-digit decimal number with decimal point, not a binary word.
This is not to be taken as a deficiency: as Perotto clearly states, the high-level instruction set was designed on purpose to make the machine easier to use. At the time the P101 was introduced no other machine had such a user-friendliness.
Anyway, it must be said that at that time the idea of "programmable calcuator" was at that time quite indifferentiated from "computer". The U.S. press coverage constantly speaks of the Programma 101 as of a computer, and unanimously stress the "desktop" nature of the P101.
Already in 1971, G.C. Bell wrote: The Programma 101 is at the limit of what we call a stored program computer.
The first programmable calculator?
But then what?
At least, its historical role is well shown by the huge number of P101s that were sold - 35.000 to 40.000. I would say this must be about as much as the sum of all the other programmable machines that had come before. It was "the first machine" for a huge lot of people, and most of the mentions you find of it is of people that say things like "I began programming in 1969, on an Olivetti Programma 101...".
Technologically, there are a few features that make it incredibly modern for the times and that are found on most programmable calculators still today, like the jump instructions that can be invoked with the press of a single key (like function keys), or the Start/Stop instruction (S) that toggles the execution status of the machine.
The magnetic cards were also a very innovative, and the patents applied on them earned to Olivetti a good deal of royalties. HP alone had to pay a total of about $900.000 for the use of the magnetic cards (and other technology) in the HP9100 series.
But why is this machine so little known?
When Perotto had the machine ready for the 1965 New York exposition, the conservative management had an enormous booth built to show off the new Logos 27 electromechanical calculators, and the P101 was hidden in a tiny room
An image from an ad.
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