К1839 is a microprocessor chipset developed between 1984 and 1989 at the Angstrem Research Institute by the same team that developed the 1801BMx series of CPUs. It was the first Soviet, and later the first Russian 32-bit microprocessor system. From a programmer's point of view, it was a complete replica of the VAX 11/750 Comet and included floating-point arithmetic, unlike the MicroVAX microprocessors produced by DEC. The chipset included a processor, a coprocessor for integer and floating-point arithmetic, a memory controller and a bus adapter. It was fabricated in a 3 µm process. The Electronika-32 computer and a VAX-PC board were built based on this chipset, as well as the aerospace on-board digital computer SB3541 (developed by LNPOEA - OKB "Electroavtomatika", St. Petersburg). The 183