Elektronika B3-34
Elektronika B3-34 (Cyrillic: Электроника Б3-34) was a Soviet programmable calculator. It was released in 1980 and was sold for 85 rubles.
B3-34 used reverse Polish notation and had 98 bytes of instruction memory, four stack user registers and 14 addressable registers. Each register could store up to 8 mantissa digits and two exponent digits in the range from 1×10−99 to 9.9999999e+99.
The first Soviet programmable stationary calculator ISKRA 123, powered by mains power, was released at the beginning of the 1970s. The first programmable battery-powered pocket calculator Elektronika B3-21 was developed by the end of 1977 and released at the beginning of 1978. Its successor, B3-34, wasn't backward compatible with B3-21. The instruction set, hardware architecture and microcode of the B3-34 defined the standard of the later Soviet programmable hand-held and office-deck calculators: MK-61, MK-52, MK-54, MK-56. Model numbers do not follow any special order: MK-54 is a slightly refurbished version of B3-34 and MK-56 is its desktop copy, while MK-61 and MK-52 are somewhat more advanced calculators with more operations and even EEPROM (MK-52 only).
Later, at the end of the 1980s, much more powerful calculators appeared on the Soviet market. For example, the calculator or hand-held computer MK-90, which had a graphic LCD display and an internal BASIC interpreter, was essentially a pocket-sized variety of the PDP-11. Due to their high price and the growing popularity of much more powerful personal computers, such as ZX Spectrum, these powerful calculators never gained popularity among the general Soviet population. Therefore, the B3-34-derived calculators are remembered by many as their "first computer".
Despite very limited capability, people managed to write all kinds of programs for B3-34 and its later successors, including adventure games and libraries of sophisticated calculus-related functions for engineers. Hundreds, perhaps thousands, of programs were written for these machines, from practical scientific and business software, which were used in real-life offices and labs, to fun games for children. During 1985–1986 the science magazine Tekhnika Molodezhi published a science fiction story "Way to Earth" accompanied by programs for B3-34 that could be used to simulate a particular segment of Moon-Earth journey from the story. The Elektronika MK-52 calculator (using the extended B3-34 command set, and featuring internal EEPROM memory for storing programs and external interface for EEPROM cards and other periphery) was used inSoviet spacecraft program (for Soyuz TM-7 flight) as a backup of the board computer.
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