1. A software entity embodied in tangible media for use with a digital design simulation model, comprising: linkages for standard logic elements for abstracting one or more design interface components out of a cycle simulation environment, and design interface emulation of interface which: (a) interacts with a hybrid cycle simulation model through the use of an API to extract the present value of the signals at the driving side of an interface, and (b) sets facilities within said hybrid cycle simulation model on the receiving side of the interface, and wherein said software entity provides an Application Program Interface for manipulating and accessing data pointers which represent a plurality of driver registers, receiver registers and bus interfaces, and further provides one propagation delay to the first part of a data transfer corresponding to a first clock edge and a same or different propagation delay to a second part of a data transfer corresponding to a second clock edge for use in a double data rate interface.