Universal serial bus implementation in an integrated access chip for ISDN systems

The universal serial bus technology comes as a response to the increasing d emands for unified interfaces and the need for flexible easy-to-use product s for personal computers. Integrating this technology into PBXs and ISDN IC s can play an important role in the integration of telecommunications and c omputer technologies The paper reports the findings of a research project c alled COPARIS for ISDN chip design with the additional USB interface. It al so presents the software and hardware design approaches for implementing US B functions in the COPARIS chip. The research indicates that a balanced app roach is the best, where the computationally intensive functions should be implemented in hardware and the rest in software.