BESM-6 at London Science Museum
|Manufacturer||Moscow Plant of Calculating and Analysing Machines (SAM)|
|Designer||S. A. Lebedev|
|Dimensions||Footprint : 150-200 m²|
|Power||30 kW @ 220 V 50 Hz|
|CPU||48-bit processor @ 9 MHz|
|Memory||Up to 192 kilobytes (32768 x 48 bits)|
|MIPS||1 MIPS |
|FLOPS||0.418 MFLOPS |
The BESM-6 was the most well-known and influential model of the series designed at the Institute of Precision Mechanics and Computer Engineering. The design was completed in 1965. Production started in 1968 and continued for the following 19 years.
Like its predecessors, the original BESM-6 was transistor-based (however, the version used in the 1980s as a component of the Elbrus supercomputer was built with integrated circuits). The machine's 48-bit processor ran at 10 MHz clock speed and featured two instruction pipelines, separate for the control and arithmetic units, and a data cache of 16 48-bit words. The system achieved performance of 1 MIPS. The fastest supercomputer at the time, the CDC 6600, achieved 2 MIPS utilizing one central and ten peripheral processing units.
The system memory was word-addressable using 15-bit addresses. The maximum addressable memory space was thus 32K words (192K bytes). A virtual memory system allowed to expand this up to 128K words (768K bytes).
The BESM-6 was widely used in USSR in the 1970s for various computation and control tasks. During the 1975 Apollo-Soyuz Test Project the processing of the space mission telemetry data was accomplished by a BESM-6 based computer complex in 1 minute. The same computation carried out by the American side would have taken approximately 30 minutes.
A total of 355 of these machines were built. Production ended in 1987.
As the first Soviet computer with an installed base that was large for the time, the BESM-6 gathered a dedicated developer community. Over the years several operating systems  and compilers for programming languages such as Fortran, ALGOL and Pascal were developed.
A modification of the BESM-6 based on integrated circuits, with 2-3 times higher performance than the original machine, was produced in the 1980s under the name Elbrus-1K2 as a component of the Elbrus supercomputer.
In 1992, one of the last surviving BESM-6 machines was purchased by the Science Museum in London, England .
The BESM-6 could send output to an АЦПУ-128 (Алфавитно-Цифровое Печатающее Устройство) printer, and read input from punched cards in the GOST 10859 character set. A Consul-254 teletype, made by Zbrojovka Brno in Czechoslovakia, could be used for interactive sessions.  When CRT terminals became available, the BESM-6 could be connected to Videoton 340 terminals .
- Savard, John J. G. (2018) . "Computer Arithmetic". quadibloc. The Early Days of Hexadecimal. Archived from the original on 2018-07-16. Retrieved 2018-07-16. (NB. Has information on the BESM-6 character set.)
- BESM-6, Russian Virtual Museum
- Electronic computers and analog devices, Grubov VI, Kirdan VS, 1977
- BESM-6 Nostalgia Page
- Simulation of Whetston benchmark on a BESM-6, retrocomputing.stackexchange.com
- Очерки по истории советской вычислительной техники и школ программирования (Издательство "Открытые Системы") Archived 2007-09-30 at the Wayback Machine
- Boris Malinovsky, Pioneers of Soviet Computing, pdf-book 2010, p. 100.
- Irina Kraineva. DISPAK - Operating System for USSR Nuclear Project. Open Systems, volume 24, number 1, 2016.
- Doron Swade, Back in the USSR, Inc. magazine, 1996
- Èlektričeskaâ pišuŝaâ mašina CONSUL 254: tehničeskoe opisanie (Electronic Writing Machine CONSUL 254: Technical description). Zbrojovka Brno, 1972.
- Laimutis Telksnys and Antanas Zilinskas. Computers in Lithuania. IEEE Annals of the History of Computing, volume 21, number 3, July-September 1999.
- The use of the "Videoton-340" video terminal with a printer on-line with the BESM-6 for electrical power network enterprise data processing. In USSR Report: Cybernetics, Computers and Automation Technology. Central Intelligence Agency, 26 December 1979.