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User:Ferrofield/Carousel memory

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Carousel memory Facit ECM 64 from Facit (2010)
Carousel memory for SMIL, now at the "Teknikens och sjöfartens hus" in Malmö, Sweden (2013)

Erik Stemme and Gunnar Stenudds created the carousel memory.[1] It was shown for the first time at a exhibition in Paris in 1958.[2]

Facit ECM 64

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The FACIT ECM 64 used another technique than a long tape. Instead 64 small rolls[3] with 9 meters,[3] 1.6 cm wide [3] tape on each roll, divided into 8 channels.[3] The tape speed is 5 m/s.[3] To read a specific roll the carousel were rotated such that the roll ended up at the bottom. A weight in the free end of the tape pulled it out and down inside a mechanism with a read- and write head. After this it was fast re-winded back. The average seek time was 2 seconds[3] and the storage space was 2560 kByte.[4] The control system were completely transistorized. Both the carousel and individual spools could be replaced.[1]

The magnetic tape used 5/8 inch (1.6 cm) wide, 0.05 mm thick Mylar 3M Co type 188.[3] The storage density is specified to 8 bits/mm[3] and the access head had the capability for simultaneous read- and write operation.[3] The power inlet requirement is 3-phase 380 volt 50 Hz and needed 300 W in standby and 750 W when active. Signaling for data used 8 parallel -20 V to 0 V 5 µs pulses.[3]

Peak transfer speed was 182 044 bits/s[4][3] using 8-parallell lines[3] and thus 22 756 bits/s per line.

The first delivery of the Facit EDB 3 computer in 1958 (to ASEA in Västerås) used the carousel memory Facit ECM 64.[5]

See also

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Further reading

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References

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  1. ^ a b Pär Rittsel (2002), Valsen inledde skivans historia [The roll initiated the disc history] (in Swedish), International Data Group (published 2010-09-11), retrieved 2016-03-22, Även om datorerna blev få så blev Erik Stemmes och Gunnar Stenudds karusellminne, stans och läsare för hålremsor stora (HTML 26 kB)
  2. ^ Magnetband till karusellminne, Föremål [Magnetic tape for carousel memory, Object] (in Swedish), Kringla, Riksantikvarieämbetet, retrieved 2016-03-22, Karusellminnet Facit ECM 64 visades första gången på en utställning i Paris 1958. Serietillverkades åren 1959-1964. (HTML 67 kB)
  3. ^ a b c d e f g h i j k l FACIT electronics AB (1961), TPU 610301 FACIT ECM 64 Karusellminne, Preliminär teknisk beskrivning [TPU 610301 FACIT ECM 64 Carousel memory, preliminary technical description] (PDF) (in Swedish), Swedish National Museum of Science and Technology (published 2012-06-15), pp. 3- (PDF 2936 kB)
  4. ^ a b FACIT electronics AB (1963), Facit Electronic presenterar FACIT ECM 64 Magnetbandsminne av karuselltyp med direkt access [Facit Electronics presents FACIT ECM 64 Magnetic tape memory of carousel type with direct access] (PDF) (in Swedish), Swedish National Museum of Science and Technology (published 2012-06-15) (PDF 2581 kB)
  5. ^ Göran Arvidsson (2002), FACIT i den tidiga dataåldern [FACIT in the early computer age] (PDF) (in Swedish) (published 2015-08-23), p. 3 (PDF 682 kB)