Design of Graphic Symbol Base for Electronic Engineering-Oriented CAD

This paper proposes a design method of defining standard graphic cell. The method makes logic clear,program easy and debugging convenient. The application of leveled model to graphic base design and its implementation are described in detail.The virtual storage technique and strategy of the multi-hierarchical storage are adopted.In our base design, many functions of the base manipulation are provided and leveled Chinese menus are fiuished, and so it makes user environment friendly. It is easy to study and manage the base.