Bistable relay computer BRC44 for education in digital technologies

  • 1 Space Research and Technology Institute – Bulgarian Academy of Sciences


The contemporary high-efficiency education in the sphere of digital technologies requires the employment of such demonstration methods and tools, which enable visual representation and illustration of the computer technologies in an attractive and accessible form. The aim is to let the learners, even if unprepared in the basic scientific and technological areas – physics, mathematics, informatics, electrical and electronic engineering, etc., easily to understand the working principle of the digital computer.
The goal of this development, the subject of the current material, is the creation of a digital computer, realized using bistable relays (BRC44). The application is with the education of students and pupils in universities and schools in the educational subjects: informatics, computer science, information technologies, electronics, and physics.
The BRC44 computer is a 4-bit computer with 4-bit data bus to the ROM memory. The employed architecture is of the Harvard type. The computer uses only bistable relays as active electronic elements without the implementation of monostable relays, vacuum electronic tubes, transistors and integrated circuits.
The bistable relay based computer is designed around four master printed circuit boards, on which are mounted the bistable relays, the semiconducting diodes, the light emitting diodes, etc.
The approbation of the BRC44 prototype with students demonstrated the easy perception of the working principle of the digital computer, due to the pictorial presentation, the light indication of the current state of each relay, etc. The computer is protected with a utility model registered at the Patent Office of the Republic of Bulgaria.



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