The development and standardisation of the OMI/HIC technology

The OMI/HIC Project (ESPRIT 7252) was established to develop a low-cost heterogeneous interconnect system for the ESPRIT-supported Open Microprocessor Systems Initiative. The objectives were to create a serial scalable interconnect technology, suitable for a wide range of processors and applications. The project concentrated on developing serial interconnect technology suitable for a range of speeds (10 Mbps to 3 Gbps) and media (copper and optic technologies). The emphasis was placed on minimising cost at both the silicon and system levels, rather than achieving the ultimate in performance, and so CMOS (and for the highest speeds, BiCMOS) manufacturing technologies were used. In order to facilitate a market for these interconnect technologies, the project catalysed the creation of IEEE Std 1355-1995 Heterogeneous InterConnect (Low Latency Low Serial Scaleable Interconnect), formalises the interface specifications of the technologies. This standard is now being taken forward as ISO/IEC 14575. This paper summarises the trade-offs made in the creation of the HIC Interconnect Technologies and recounts the benefits, expected and unexpected, of the international standardisation work.