The Olivetti Programma 101(curtamania.com)
curtamania.com
The Olivetti Programma 101
http://www.curtamania.com/curta/database/brand/olivetti/Olivetti%20Programma%20101/index.html
9 comments
I think the most interesting feature of old desktop calculators was the use of the
'magnetostrictive metal wire acoustic delay line' for memory.
That is super cool, I've never heard of acoustic memory before.
Using a transducer a series of acoustic pulses (bits) are inserted into one end of the wire. The pulse travels along the wire at the sound speed and reach the other end where the signal is "read"
2000 bits with 6.5m of wire. You could make a 128GB flash card equivalent with only 416,000 km of wire (a bit over the distance from the Earth to the Moon)
Using a transducer a series of acoustic pulses (bits) are inserted into one end of the wire. The pulse travels along the wire at the sound speed and reach the other end where the signal is "read"
2000 bits with 6.5m of wire. You could make a 128GB flash card equivalent with only 416,000 km of wire (a bit over the distance from the Earth to the Moon)
In fact the pulse travelled slower than the speed of sound. Thereby fitting more bits on the same length of wire. The transducer twisted the wire, so a rotational pulse spiraled down the wire. This takes longer time than a purely axial sound pulse.
We had one of these in my school in the seventies. I remember using it although I can't recall the technical details now other than it being extremely limited.
My dad was a civil engineer who loved computing so had the luck to be exposed to all his purchases. Memorable for me this Programma 101, an HP-67 (could be programmed with magnetic strips! And had Polish notation :), a couple of Olivetti M24 with GWBasic as OS...
(Reverse Polish Notation; RPN)
What were typical applications of these computers? And who programmed it?
The only thing they say is, The Programma 101 was used in important projects of that time like the Apollo project at NASA... Also: Usually this machine is called "programmable calculator"... As I remember, these were popular (in a much more compact form) through the 70s - 90s.
Later, in 1969, I used the HP9100A desktop calculator. This was a 30kg HP35 with 196 steps of memory, a CRT which showed either 3 steps of the program, or the three rpn registers. It was the successor to the Programma, and was replaced by a series of desk calculators with more memory, LED displays, the ability to control analog plotters, and ultimately BASIC programming.
But the value of the early calculators like the Programma was in teaching efficient algorithm design with limited memory. While this was completely obviated in scientific programming by the late 70’s, I’m sure it served as a first introduction to software engineers writing in assembly language.