Provides the mechanical, electrical and signalling protocol specifications for an efficient simplex high-performance point-to-point interace between pieces of data-processing equipment. The interface described in this document can be operated at peak data rates of 800 or 1600 Mbit/s, over distances of up to 25m by means of copper cabling. A distance-independent signalling protocol allows the average data rates to approach the peak data rates, even over distances longer than specified for the HIPPI-PH.