The First Lithuanian Accounting Machine

 

by Gintautas Grigas,

 

Assoc. Prof. Dr. Gintautas Grigas is an emeritus senior researcher at the Informatics Methodology Department, Institute of Mathematics and Informatics (MII). He is a founder of the Extramural School of Young Programmers in 1981, former head of the Programming Methodology Department of MII, author of 30 books on programming, programming languages, teaching informatics, (three books translated into Russian, one in Polish) and author of some 100 scientific papers and numerous science popularization articles.

 

In 1948 IBM launched the production of the highly successful accounting machine IBM 604. Ten years later a similar machine was designed in the Soviet Union  and named EV80. The production of EV80 was carried out in the SAM factory in Moscow and at the Lithuanian factory VSMG (Vilnius Electronic Computer Factory). The machines of such class consist of two devices: electronic processor and electro-mechanical punch-card input-output device.

The feedback of EV80 users had shown that the work of the machine was not stable, there were problems with the short age of vacuum tubes. The first work of Vilnius SKB (Special Design Bureau), established in 1959, was to modernize EV80.

In 1959 a team consisting of Feliksas Atstopas, Stasys Girliavičius, Gintautas Grigas, Steponas Janušonis, Algis Petrauskas, Kęstutis Ramanauskas, Donaldas Zanevičius and Romualdas Žlabys under the leadershif of Antanas Nemeikšis began with the modernization of EV80. It was decided to decrease the number of vacuum tubes, to change the construction of hardware cells and provide more reliable connectors. At that time, the quality of semiconductor diodes was sufficient enough for logic gates but the parameters of the transistors were not stable. Thus the diodes were used for AND and OR gates but vacuum tubes remained in inverters (NOT cells) and memory elements (flip-flops). The machine was named by EV80M.

Already during the working phase on the project we gradually realized that the machine was below our expectations and it became obvious that the hardware based on vacuum tubes has no future. Only a single experimental copy of EV80 was produced.

We were looking for other ways simultaneously and we came to the conclusion that it is possible to design entirely new machine based on ferrite-transistor elements, not requiring extra stability of transistor parameters. While working on EV80M we worked on a new project. Alfonsas Lipnickas, Jonas Puodžius, Regina Valatkaitė, and others joined our team.

The new machine was named by Rūta after the name of Lithuanian national flower rue (lat. ruta graveolens).

The parameters of machine were close to those of EV80 (or IBM 604), but construction and logical circuits were entirely different. The circulation of data was dynamic, decimal digits were coded by the code 8421+3, ensuring higher stability of performance.

On December 23, 1962 after exhaustive testing the Joint Test Commision decided that Rūta was ready for production. Rūta was produced at the Vilnius Electronic Computer Factory until 1974 and 702 units were produced in total. The attractive features of the machine were simplicity of its maintenance and low price, of course, relatively to other machines of that time.

Rūta was exported to other Soviet republics and also to Bulgaria, Czechoslovakia, Germany, Poland and Romania.

The successful project was important itself. In addition, this was the starting point for other Lithuanian computers: Rūta 110, M5000, M5100, SM1600, SM1700.

 

 

 

Processor (left) and input-output punched card device (right) among the some members of the team

 

IT STAR, 2008, v. 6, nr. 1, p. 7.