Motorola Inc’s Microprocessor & Memory Technologies Group has announced its next generation Fibre Distributed Data Interface chip set, which reduces the number of parts to two from four. The company has also announced its participation in a demonstration by 13 companies of the interoperability between their FDDI over Unshielded Twisted Pair products. Designed to conform to ANSI standards for both fibre and twisted-pair cabling, the new chip set comprises the 68840 Integrated Fibre Distributed Data Interface and the 68836 FDDI Clock Generator. It is the IFDDI chip where Motorola has managed to achieve most of the space savings. This integrates three of the four original components: the Elasticity Buffer-Link Manager, the Media Access Controller and the FDDI System Interface. In addition, Motorola is offering the 68834 Cipher Chip which – used with the chip set – provides support for the emerging ANSI Twisted-Pair Physical Medium Dependent twisted-pair wiring standard. Motorola claims several performance-enhancing features for its IFDDI, including two 32-bit ports enabling system transfer speeds of over 200Mbps on the system bus, 8Kb memory, and support for bursting buses. The IFDDI also features port-to-port Direct Memory Access capability between the two 32-bit ports – which is claimed to eliminate the need for a local processor and relieve latency requirements for implementing high-speed networks – while the company also says that the data ports can be used separately or combined to implement 32- or 64-bit system interfaces, enabling it to be incorporated into non-FDDI applications such as high-speed serial interfaces. Through the IFDDI, Motorola says the chip set can be interfaced to any standard system bus including SBus, Peripheral Component Interconnect, Micro Channel, EISA, AT and VME as well as to any microprocessor including its 68000, 88000 and PowerPC families. It can also interface to other chip architecture such as iAPX-86, R-series and Sparc. In quantities of 5,000, the chip set is priced at around $100. The local network-based interoperability demonstration of FDDI over unshielded twisted pair included transceivers, hubs, concentrators and personal computer and workstation adaptors. The companies taking part were 3Com Corp, Cabletron Systems Inc, Codenoll Technology Inc, Crescendo Communications Corp, Digital Equipment Corp, Interphase Corp, Micro Linear Corp, Motorola Data Communications, Network Peripherals Inc, Pulse Engineering Inc, Silicon Graphics Inc, SynOptics Communications Corp and Technitrol Inc.
