BESM (БЭСМ) is the series of Soviet

mainframe A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterpris ...

computers built in 1950–60s. The name is an acronym for "Bolshaya (or Bystrodeystvuyushchaya) Elektronno-schotnaya Mashina" ("Большая электронно-счётная машина" or "Быстродействующая электронно-счётная машина"), meaning "Big Electronic Computing Machine" or "High-Speed Electronic Computing Machine". It was designed at the Institute of Precision Mechanics and Computer Engineering

Models

The BESM series included six models.

BESM-1

''BESM-1'', originally referred to as simply the BESM or BESM AN ("BESM Akademii Nauk", BESM of the Academy of Sciences), was completed in 1952. Only one BESM-1 machine was built. The machine used approximately 5,000

vacuum tube A vacuum tube, electron tube, thermionic valve (British usage), or tube (North America) is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. It ...

s. At the time of completion, it was the fastest computer in Europe. The floating-point numbers were represented as 39-bit

word A word is a basic element of language that carries semantics, meaning, can be used on its own, and is uninterruptible. Despite the fact that language speakers often have an intuitive grasp of what a word is, there is no consensus among linguist ...

s: 32 bits for the mantissa, one bit for sign, and 1 + 5 bits for the exponent. It was capable of representing numbers in the range 10⁻⁹ – 10¹⁰. BESM-1 had 1024 words of read–write memory using ferrite cores, and 1024 words of

read-only memory Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing sof ...

based on semiconducting diodes. It also had external storage: four

magnetic tape Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnetic ...

units of 30,000 words each, and fast magnetic drum storage with a capacity of 5120 words and an access rate of 800 words/second. The computer was capable of performing 8–10 K

Flops Floating point operations per second (FLOPS, flops or flop/s) is a measure of computer performance in computing, useful in fields of scientific computations that require floating-point calculations. For such cases, it is a more accurate measu ...

. The energy consumption was approximately 30 kW, not accounting for the cooling systems.

BESM-2

''BESM-2'' also used

BESM-3M and BESM-4

''BESM-3M'' and ''BESM-4'' were built using

transistors A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electric power, power. It is one of the basic building blocks of modern electronics. It is composed of semicondu ...

. Their architecture was similar to that of the M-20 and M-220 series. The word size was 45 bits. Thirty BESM-4 machines were built. BESM-4 was used to create the first ever

computer animation Computer animation is the process used for digitally generating Film, moving images. The more general term computer-generated imagery (CGI) encompasses both still images and moving images, while computer animation refers to moving images. Virtu ...

. The prototypes of both models were made in 1962–63, and the beginning of the series release was in 1964.

EPSILON Epsilon (, ; uppercase , lowercase or ; ) is the fifth letter of the Greek alphabet, corresponding phonetically to a mid front unrounded vowel or . In the system of Greek numerals it also has the value five. It was derived from the Phoenic ...

(a macro language with high-level features including strings and lists, developed by Andrey Ershov at

Novosibirsk Novosibirsk is the largest city and administrative centre of Novosibirsk Oblast and the Siberian Federal District in Russia. As of the 2021 Russian census, 2021 census, it had a population of 1,633,595, making it the most populous city in Siber ...

in 1967) was used to implement

ALGOL 68 ALGOL 68 (short for ''Algorithmic Language 1968'') is an imperative programming language member of the ALGOL family that was conceived as a successor to the ALGOL 60 language, designed with the goal of a much wider scope of application and ...

on the M-220.

BESM-6

The BESM-6 was the best-known and most influential model of the series. The design was completed in 1965. Production started in 1968 and continued for the following 19 years.Очерки по истории советской вычислительной техники и школ программирования (Издательство "Открытые Системы")
ssays on the history of Soviet computer technology and programming schools (Open Systems Publishing) (in Russian),
Google translation

Models

BESM-1

BESM-2

BESM-3M and BESM-4

BESM-6

See also

References

Further reading