UKNC

UKNC (Elektronika MS-0511)

Company type	Educational microcomputer
Industry	Computer hardware
Headquarters	Zelenograd , Soviet Union
Products	UKNC microcomputer

UKNC (), also referred to as Elektronika MS-0511, is a Soviet-era educational microcomputer compatible with the PDP-11 architecture. Developed by the Scientific Centre in Zelenograd, it was intended for use in teaching informatics within schools. Production totaled around 310,000 units, manufactured across five different Soviet plants located in Russia, Lithuania, Georgia, and Moldova.

Hardware

• Central processor: KM1801VM2 1801 series CPU operating at 8 MHz, featuring a 16-bit data bus and a 17-bit address bus
• Auxiliary processor: KM1801VM2 running at 6.25 MHz, responsible for managing peripheral hardware and executing user-level programs
• Memory specifications: 64 KiB of CPU RAM, 32 KiB dedicated to the peripheral processor, 32 KiB ROM, and 96 KiB video RAM arranged in three planes
• Display capabilities: maximum resolution of , supporting up to 53 simultaneous colors; palette and resolution adjustable on a per-line basis; lacks a dedicated text mode
• Input device: an 88-key keyboard (model MS-7007) utilizing the JCUKEN layout
• Interfaces: integrated LAN controller alongside a tape-recorder interface commonly paired with 5-inch floppy disk drives

The architecture includes a peripheral processing unit (PPU) designed to handle device control tasks separately from the main CPU, thereby improving overall system efficiency. The chassis and keyboard design draw inspiration from the Yamaha MSX standard, which had been widely adopted in Soviet educational institutions. This enclosure was also employed for the IBM PC-compatible Elektronika MS-1502 and the Rusich learning computer.

There are three versions of the model: 0511, 0511.1 tailored for domestic use with a 220 V AC power input, and 0511.2, which incorporates updated firmware along with modified keyboard labeling. The 0511.2 lacks active cooling mechanisms and may experience overheating during prolonged operation.

Software

• Operating systems: RAFOS, FODOS (both RT-11 derivatives), RT-11SJ/FB
• LAN management software
• Programming environments:
  • BASIC (Vilnius BASIC)
  • Fortran
  • Pascal
  • Modula-2
  • C
  • Assembly language
  • Rapira
  • E-practicum
  • Logo
  • Prolog
  • Forth
  • FOCAL