Editing Kronos (computer)

{{Short description|Mid-1980s Soviet 32-bit graphical workstation}}
{{More citations needed|date=December 2013}}
{{Use dmy dates|date=March 2021}}
{{Infobox information appliance
| name = Kronos
| title = 
| aka = 
| logo = 
| image = 
| caption = 
| developer = [[Academy of Sciences of the Soviet Union]], Siberian branch, [[Novosibirsk]] Computing Center, Modular Asynchronous Developable Systems (MARS) project, Kronos Research Group (KRG)
| manufacturer = 
| family = [[Niklaus Wirth|Wirth]] [[Lilith (computer)|Lilith]]
| type = [[workstation]]
| generation = 
| release date = {{Start date and age|1988}}
| retail availability = none
| lifespan = 
| price = 
| discontinued = Yes
| units sold = 
| units shipped = 
| media = 
| os = Excelsior
| power = 
| soc = 
| cpu = [[32-bit computing|32-bit]]
| storage = 
| memory card = 
| display = [[monochrome]] [[Raster graphics|bitmapped]]
| graphics = 
| sound = 
| input = 
| controllers = 
| camera = 
| touchpad = 
| connectivity = 
| currentfw =
| platform = 
| service = 
| dimensions = <!-- {{convert|##|x|##|x|##|in|cm|abbr=on}} -->
| weight = 
| topgame = 
| compatibility = 
| predecessor = 
| successor = 
| related = 
| marketing_target = Research
| website = {{URL|kronos.ru}}
}}
'''Kronos''' is a series of [[32-bit computing|32-bit]] processor equipped [[printed circuit board]] systems,<ref name="Kronos-xTech">{{Cite web |title=Kronos: History of a Project |url=http://www.kronos.ru/ |date=<!-- Undated --> |publisher=xTech |language=ru |access-date=8 April 2021}}</ref> and the [[workstation]]s based thereon,<ref name="Kronos-xTech"/> of a [[proprietary hardware]] architecture developed in the mid-1980s in [[Akademgorodok]], a research city in [[Siberia]], by the [[Academy of Sciences of the Soviet Union]], Siberian branch, [[Novosibirsk]] Computing Center, Modular Asynchronous Developable Systems (MARS) project, Kronos Research Group (KRG).<ref name="Kronos-xTech"/><ref>{{Cite journal |last1=Kuznetsov |first1=D.N. |last2=Nedorya |first2=A.E. |last3=Osipov |first3=A.V. |last4=Tarasov |first4=E.V. |date=1986 |editor-last=Kotov |editor-first=V.E. |title=The processor Kronos in a multiprocessor system |journal=Computer Systems and Software |place=Novosibirsk |pages=13–19 |language=ru}}</ref><ref>{{Cite journal |last1=Wolcott |first1=P. |last2=Goodman |first2=S.E. |date=September 1988 |title=High-Speed Computers of the Soviet Union |journal=Computer |publisher=[[Institute of Electrical and Electronics Engineers]] |volume=21 |issue=9 |pages=32–41 |doi=10.1109/2.14345|s2cid=15721973 }}</ref>

==History==
In 1984, the Kronos Research Group (KRG) was founded by four students of the [[Novosibirsk State University]], two from the mathematics department (Dmitry "Leo" Kuznetsov, Alex Nedoria) and two from the physics department (Eugene Tarasov, Vladimir Vasekin). At that time, the main objective was to build home computers for the KRG members.{{Citation needed|date=December 2013}}

In 1985, the group joined the Russian fifth generation computer project START, in which Kronos became a platform for developing multiprocessor reconfigurable ''Modular Asynchronous Developable Systems'' (MARS),<ref>{{Cite journal |last=Kotov |first=V.E. |date=1991 |title=Concurrency + modularity + programmability = MARS |journal=Communications of the ACM |volume=34 |issue=5 |pages=32–45|doi=10.1145/103701.103707 |s2cid=10320717 |doi-access=free }}</ref> and played a lead role in developing the first Russian full 32-bit workstation and its software.{{Citation needed|date=December 2013}}

During 7 years (1984–1991) the group designed and implemented:{{Citation needed|date=December 2013}}

* Kronos 2.1 and 2.2 – 32-bit processor boards for DEC LSI-11
* Kronos 2.5 – 32-bit processor board for Labtam computers
* Kronos 2.6 – 32-bit workstation

The project START was finished in 1988. During the post-START years (1988–1991), several Russian industrial organizations expressed interest in continuing the Kronos development and some had been involved in facilitating the construction of Kronos and MARS prototypes, including the design of a Kronos-on-chip. However, changing funding levels and the chaotic economic situation during [[perestroika]] kept those plans from being realized.{{Citation needed|date=December 2013}}

==Architecture==
The Kronos [[instruction set architecture]] was based on [[Niklaus Wirth]]'s [[Modula-2]] workstation [[Lilith (computer)|Lilith]], developed at the Swiss Federal Institute of Technology ([[ETH Zurich]]) of [[Zürich]] Switzerland, which in turn was inspired by the [[Xerox Alto]] developed at [[Xerox PARC]].<ref name="Kronos-xTech"/>

The Modula-2-based Kronos was quite amenable to the basic principles of MARS, as Modula-2 is fundamentally modular, allowing programs to be partitioned into units with relatively well defined interfaces. These interfaces supported separate compiling of modules, and separating of module specifications from their implementation. The primary difference between Lilith and Kronos was that the processor of Lilith was [[16-bit computing|16-bit]], while Kronos was 32-bit and incorporated several extensions to the instruction set to accommodate the inter-processor communication needed in MARS.{{Citation needed|date=December 2013}}

Kronos satisfied many aspects of the [[reduced instruction set computer]] (RISC) design, although it was not pure RISC: the evaluation stack was used to evaluate expressions and to hold parameters for procedure calls. Since most executed instructions were encoded in a single byte, the object code for Kronos was very compact. Although Kronos was a proprietary processor, it was well suited to applications which were sensitive to high programmability rather than to software compatibility. For example, embedded control systems require fast and reliable design of new original applications for controlling unique objects and processes. Modula-2 was then a perfect language for this purpose, and Kronos was a perfect processor to effectively run the Modula-2 software.{{Citation needed|date=December 2013}}

==Hardware==
An advanced version of Kronos was based on a 32-bit stack-type КА1845ВМ1 processor, КА1845ВС1 data processing unit, and УУП memory control unit. All the three were designed and fabricated by КНИИМП, Kiev Research Institute of Microdevices.
* [http://www.155la3.ru/k1845.htm КА1845ВМ1] had 246 commands, which allowed supporting Modula-2 language. It also featured hardware support of interrupts and process synchronization. The CPU was fabricated in a 2.5 um CMOS technology with two layers of metallization and packaged in a planar 84-pin metal-polymer case. It contains 199 thousands elements and has area of 8.55x8.1 mm^2. The maximum clock frequency is 10 MHz.
* [http://www.155la3.ru/k1845.htm КА1845ВС1] contained ALU, 8x32 stack, matrix shifter, 16x32 register block, and status flag multiplexers. The amount of addressable memory is 4 GB. The chip area is 5.8x5.25 mm^2, 16 thousand elements.
* [http://www.155la3.ru/uup.htm УУП] provided operation with virtual memory up to 4 GB. It contains a data cache (128x32), a redirect buffer (128x40), a dynamic RAM controller, and an error detection and correction circuit. Memory access time does nor exceed 100 ns. УУП chip contains 102 thousands elements and has area of 9.1x7.3 mm^2.

==Software==
The Kronos software included:{{Citation needed|date=December 2013}}
*Versions of the proprietary operating system Excelsior
*Compilers for Modula-2, [[C (programming language)|C]], and [[Fortran]]
*CAD systems
*Other applications

===Operating system===
{{Infobox OS
| name = Excelsior
| logo = <!-- Filename only: no wikilink, Image: or File: -->
| logo size = 
| logo caption = 
| logo alt = 
| screenshot = <!-- Filename only: no wikilink, Image: or File: -->
| caption = 
| screenshot_alt = 
| developer = Kronos Research Group (KRG)
| family = 
| working state = Discontinued
| source model = [[Proprietary software|proprietary]]
| released = {{Start date and age|1988}}<!-- If known, add |mm|dd|df=yes -->
| discontinued = Yes
| latest release version = 
| latest release date = <!-- {{Start date and age|199y|mm|dd|df=yes}} -->
| marketing target = Research
| programmed in = [[Modula-2]]
| language = Russian
| update model = Compile from [[source code]]
| package manager = Modula-2 modules
| supported platforms = Kronos
| kernel type = [[Modular programming|Modular]]
| userland = 
| ui = 
| license = 
| preceded by = [[Lilith (computer)#Operating system|Medos-2]]
| website = {{URL|www.kronos.ru/literature/processors}}
| other articles = 
}}
The Kronos workstation includes an [[operating system]] named ''Excelsior'', developed by the Kronos Research Group (KRG). It is a single user system based on Modula-2 modules.<ref name="Kronos-Excelsior">{{Cite web |last1=Kuznetsov |first1=D.N. |last2=Nedorya |first2=A.E. |last3=Tarasov |first3=E.V. |last4=Filippov |first4=V.E. |date=<!-- Undated --> |title=Kronos: a family of processors for high-level languages |url=http://www.kronos.ru/literature/processors |website=Kronos: History of a Project |publisher=xTech |language=ru |access-date=13 April 2021}}</ref>

In design, it is similar to the OS ''[[Lilith (computer)#Operating system|Medos-2]]'', developed for the Lilith workstation, at ETH Zurich, by Svend Erik Knudsen with advice from Niklaus Wirth.<ref>
{{Cite thesis |last=Knudsen |first=Svend Erik |date=1983 |title=Medos-2: A Modula-2 Oriented Operating System for the Personal Computer Lilith |type=PhD |publisher=[[ETH Zurich]] |doi=10.3929/ethz-a-000300091}}<!-- also at http://e-collection.library.ethz.ch/eserv/eth:21975/eth-21975-02.pdf --></ref><ref>
{{Cite book |last=Knudsen |first=Svend Erik |date=25 October 2000 |chapter=Medos in Retrospect |editor1-last=Böszörményi |editor1-first=László |editor2-last=Gutknecht |editor2-first=Jürg |editor2-link=Jürg Gutknecht |editor3-last=Pomberger |editor3-first=Gustav |title=The School of Niklaus Wirth: The Art of Simplicity |pages=69–86 |publisher=Morgan Kaufmann |isbn=978-1558607231}} {{ISBN|1-55860-723-4}} & dpunkt, {{ISBN|3-932588-85-1}}.</ref>

==References==
{{Reflist}}

==External links==
* {{Official website|kronos.ru}}, history in Russian
* [https://web.archive.org/web/20180108143100/https://www.excelsior-usa.com/krg/krg.html The Kronos Research Group] recovered from [[Internet Archive]]
* [http://www.modulaware.com/mdlt52.htm A Brief History of Modula and Lilith]
* [http://www.inc.com/magazine/19960615/1967.html Acquisition of a Kronos workstation and more by the National Museum of Science and Industry in London]
* [http://code.google.com/p/kronos/ Historical source code from Kronos 198x USSR 32-bit workstation]
*[https://web.archive.org/web/20160408011809/http://www.excelsior-usa.com/krg/full-kronos.zip Emulator for the Kronos workstation] (via Internet Archive) runs on Windows-NT; tested thereon successfully. Two logins are possible: <code>sys</code> or <code>guest</code>, both password free. See also: [http://kronos.ru/documentation More Documentation of Kronos in Russian]

{{Modula, Oberon}}
{{List of Soviet computer systems}}
{{Russian operating systems}}

{{DEFAULTSORT:Kronos (Computer)}}

[[Category:Computer workstations]]
[[Category:Soviet computer systems]]