US Patent 8438524 Hierarchical editing of printed circuit board pin assignment

An interface object library tool for manipulating interface objects for a printed circuit board (PCB) tool is disclosed. The interface object library tool includes a hierarchical interface display module, an input module, and a store. The hierarchical interface display module is configured to display an interrelation between a plurality of interface objects and a plurality of groups each including a plurality of signal, power and ground lines. The plurality of interface objects are configured to be associated with a plurality of block objects to define a plurality of component objects. The input module is configured to: accept association of the plurality of groups and the plurality of signal, power and ground lines without defining pin or pad assignments; and accept association between the plurality of interface objects and a plurality of groups. The store is configured to retain the plurality of interface objects; the plurality of groups; the plurality of signal, power and ground lines; and associations between these three.