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Time Sharing Operating System

Operating System

TSOS, the Time Sharing Operating System, was an operating system RCA designed in 1968 for its Spectra 70/46 mainframe within the Spectra 70 series, offering time-sharing features similar to CTSS along with a unified interface for both time-sharing and batch processing. It evolved by 1970 into the Virtual Memory Operating System, VMOS, and after RCA left the computer business in 1971, Sperry Corporation acquired the division and renamed the system VS/9; Siemens later built an enhanced variant, BS2000, which Fujitsu still supports today as BS2000/OSD for customers in Europe. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Classification
License
Proprietary (Closed Source) 1
Status
Status
Discontinued 1
Year
1968 2
FAQs

How is the Time Sharing Operating System related to BS2000?

BS2000 grew out of TSOS.

BS2000 has its roots in TSOS. A history of BS2000 on the German site F10479 says RCA first developed TSOS for the Spectra 70 series. Siemens later took over development on its own and sold a system built on TSOS. The same source says UNIVAC also used TSOS under the name VS/9 for its series 90 mainframes.

Which computer architecture was the RCA Spectra 70 line modeled on?

IBM's S/360 architecture.

According to the F10479 history of BS2000, the Spectra 70 line of the late 1960s was modeled on the architecture of IBM's S/360 series. The same source says RCA stopped producing and developing hardware and software after a patent dispute with IBM.
Connections

In Field

Source Wikipedia: Time Sharing Operating System

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Developed By

Also in Business Atlas: the developer of this subject.

Sources
1. Wikipedia: Time Sharing Operating System
  • Infobox: license
    Proprietary
  • In Field: Operating Systems, Lead sentence
    Time Sharing Operating System, or TSOS, is a discontinued operating system for RCA mainframe computers of the Spectra 70 series.
View the Source
2. Wikidata: Time Sharing Operating System
  • Wikidata Q2384995, class allow-list match (w-wdresolver-0926)
  • Wikidata Q2384995 P577 (publication/release date) claim -> 1968; checked 2026-09-28
View the Source
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