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. 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 CDC 6600, a common Western supercomputer when the BESM-6 was released, achieved about 2 MIPS. The system memory was word-addressable using 15-bit addresses. The maximum addressable memory space was thus 32K words. A virtual memory system allowed to expand this up to 128K words. The BESM-6 was widely used in USSR in the 1970s for various computation and control tasks. During the 1975Apollo-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.
Peripherals
The BESM-6 could send output to an АЦПУ-128 printer, and read input from punched cards in the GOST 10859character 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.
