Component Composition Technology's Application In Digital Circuit Virtual Lab

Component-based software reuse (CBSR) is an important approach to achieve engineering software development and industrialized software production, and component composition is a key point. The target of component composition is fully reusing existing components to assemble into a larger size component or a full system. Due to the Chip's features of complex and diversity in Hardware experimental, a method of developing digital circuit virtual laboratory using component composition was presented.Firstly, a chip model was designed and a method of developing virtual chips based on XML was presented, which can construct specific chip components from the XML that configured in visualization. Based on the logic truth tables and function features tables of digital circuits, the realization of combinational logic circuits and sequential logic chips are described in detail.Secondly, for the working principle and structure of the circuit chip, a component composition based on thread-tree was presented. The pin map between composite components and atom components were stored in thread-tree. By the thread-tree a method of decomposing composite chips layer-by-layer was implemented, which allows users observe the internal structure of the chip visually and better understand the chip's design. At the same time, the interest in the experiment was increased.Finally, for the running features of highly asynchronous and concurrent of hardware, a component scheduling mechanism based on data-driven was presented. Simulation of the hardware running was implemented effectively.The practice shows that the proposed method can effectively simplify the development of virtual chips in hardware virtual lab, and the method of component composition provides a good reference to the development of other virtual lab.