Tremendous achievements in the area of semiconductor electronics turn - croelectronics into nanoelectronics. Actually, we observe a real technical boom connected with achievements in nanoelectronics. It results in devel- mentofverycomplexintegratedcircuits,particularlythe?eldprogrammable logic devices (FPLD). Up-to-day FPLD chips are so huge, that it is enough only one chip to implement a really complex digital system including a da- path and a control unit. Because of the extreme complexity of modern - crochips, it is very important to develop e?ective design methods oriented on particular properties of logic elements. The development of digital s- tems with use of FPLD microchips is not possible without use of di?erent hardware description languages(HDL), such as VHDL and Verilog. Di?erent computer-aided design tools (CAD) are wide used to develop digital system hardware. As majorityof researchespoint out, the design processis nowvery similar to the process of program development. It allows a researcher to pay more attention to some speci?c problems, where there are no standard f- mal methods of their solution. But application of all these achievements does not guaranteeper sedevelopmentof some competitiveelectronic product,- pecially in the acceptable time-to-market. This problem solution is possible only if a researcher possesses fundamental knowledge of a design process and knows exactly the mode of operation of industrial CAD tools in use. As it is known, any digital system can be represented as a composition of a da- path and a control unit.