K-202 was a 16-bit minicomputer, created at Elwro by team led by Polish scientist Jacek Karpiński between 1971–1973 in cooperation with British companies Data-Loop and M.B. Metals. Approximately 30 units were claimed to be produced. All units shipped to M.B. Metals were returned for service; later the company dropped out of contract due to Elwro being unable to fulfill its obligations. At that point Karpiński decided to leave the company. The K-202 had two main rivals Data General SuperNOVA minicomputer (United States) and the CTL Modular One (United Kingdom).
Some time after the K-202 was reimplemented as MERA-400, hundreds of units of which were built.
The K-202 was capable of running about one million operations per second; however, its instruction set was not well suited to the typical tasks, making practical performance somewhat lower. Although the communist world was decades behind the West in integrated circuit manufacture, the export of which was (and still is) strictly controlled. Despite this, apparently, remarkable performance and low price there was no commercial interest from anywhere in the world. K-202 claimed to be the first mini-computer which used the paging technique, providing 8 MB of virtual memory; however, what its constructors called paging was in fact a simple segmentation. Furthermore, the advertised upper limit of 8MB of memory was practically unreachable due to signal propagation delays, 144 KB being the largest available configuration. K-202 was based on small- and medium-scale integrated circuits.
- 16-bit word
- More than 90 instructions
- 7 universal registers
- 16 ways of determining argument
- Operating memory of up to 4 million words
- Direct addressing of up to 64k words
- Autonomic data exchange with operating memories at the speed of 16 Mbit/s [note: i.e. 1M words/s]
- Implementation method – TTL/MSI integrated circuits
- Memory cycle 0.7 μs
- Processing speed of 1 million operations/second
- K-202 factsheet in Polish
- Broszura informacyjna minicomputer K-202 (Polish)
- PDF in Polish and English:
- Reklamówka z MTP Poznań 1971 (Polish)
- Brochure K-202 w j. angielskim z MTP Poznań 1971 in (English)
- "Maszyna cyfrowa K-202 – organizacja logiczna" – scholar materials (Polish)
- "Język operacyjny maszyny – JOM 1" – scholar materials (Polish)
- "Opis podstawowego języka symbolicznego M.C. K-202 – ASSK" – scholar materials (Polish)
- "System programowania minikomputera K-202 w języku Lisp 1.5. Instruction for programists, Poznań Instytut Automatyki Politechniki Poznańskiej 1974 (Polish)
- "60 lat polskich komputerów. Historia romantyczna" 
- MERA-400, K-202 reimplementation