Abstract: Since a plurality of electric CAD systems (CAD) 1 generate circuit diagram data with different data structures, input interface (IF) software (SOFT) implements processing for extracting predetermined item data used in parts selection SOFT from each CAD, and processing for adding data obtained by the parts selection SOFT to each CAD. The parts selection SOFT implements selection of parts, output of slips, and the like on the basis of the predetermined item data. Output IF-SOFT converts information associated with the selected parts output from the parts selection SOFT into a different data format used in the subsequent process, and outputs the converted information.

Abstract: The steps for designing a complex object of design are centralized, and the setting for processing programs started with the steps is greatly simplified, so that the load on the designer is reduced, and errors in design are also reduced. To that end, in the event of designing an object of design by a plurality of steps, the plurality of steps are displayed on a CRT display, judgment is made whether execution thereof is possible, and based on that judgment, executable steps are displayed in green, and non-executable steps are displayed in red. Setting of the parts necessary for design, and the setting of CAD tools started in the steps is performed by keyboard or mouse, and the steps of which the state has change are identified, and the color thereof is changed.