SwiftNet the really fast, truly synchronous fieldbus A Brief Introduction to SwiftNet SwiftNet is the modern, high performance fieldbus. It was created to satisfy Boeing Commercial Airplane"s need for a truly synchronous, very high speed (an unequaled 85K samples/sec) flight data bus. SwiftNet goes well beyond this mission, as it also locks the local clocks of all fieldbus nodes together and time stamps all alarms and alerts at their source, to eliminate time aliasing of event reports. This effectively eliminates the jitter and irregular schedules that loom so large in popular fieldbuses. Uniquely SwiftNet provides synchronous global, group and individual triggers to stimulate device actions. Because triggers use each device"s local clock, they do not reduce the data transfer rate on the bus. These highly desirable behaviors result from the SwiftNet"s use of a structured, synchronous (TDMA) bus protocol which eliminates addresses from all packets and guarantees synchronous operation of all nodes. The Producer Consumer paradigm further improves both performance and flexibility. SwiftNet supports a variety of application protocols, including FMS and ControlNet/DeviceNet Objects. A highly efficient granulation protocol supports application data packets that range from 64 to 896 bytes. Application packets do not disturb data transfer timing. Currently bus lengths and speeds for RS485 range between: Maximum length of an Unbridged Fieldbus Bus Data Rate 4800 meters 2.4 to 76 Kbs 340 meters 5 Mbs Fiber Optic media are also supported. Bus configuration is totally end-user defined. It is automatically performed and checked each time the bus is powered-on. This allows easy conversion between missions, as in laboratory or test environments. SwiftNet also synchronizes multiple bridged networks with up to 30,000,000 nodes and up to 100,000,000 total variables. Synchronism between nodes is maintained to an unmatched 50 sec. SwiftNet and Enterprise Networks SwiftNet is an ideal interface between devices and enterprise networks that use IP or other network protocols, since it maintains fieldbus schedules and synchronism without software intervention. This effectively eliminates the effect of network delays on device performance and data/event reports and helps compensate for non real-time operating systems such as Windows NT. SwiftNet Architecture SwiftNet"s low cost architecture uses a SwiftNet ASIC with a DPRAM interface to each smart instrument"s microprocessor. This ASIC performs all protocol functions to guarantee true interoperability between vendors. This approach substantially reduces device cost, size and power consumption. Host devices use the SwiftNet ASIC along with a block of memory for each field device. As device counts rise, a host can consume significant resources. SwiftNet Applications SwiftNet shines in applications that need one or more of the following characteristics: high speed, synchronous data acquisition or control, high point count, wide area coverage and/or need an interface to enterprise networks. Some applications where SwiftNet is a clear favorite include: flight test, flight simulation, fly by wire, direct numerical control, operation of complex machines and systems oil platforms, oil fields & wells, exploration, undersea, mining, office complexes, any campus and transportation systems. SwiftNet Properties SwiftNet is a very high efficiency / high scan rate, truly-synchronous fieldbus. SwiftNet allows very high speed analog I/O (up to 85,000 16 bit samples per sec. at a 5 Mbs data rate) to share one bus with a large number of discrete I/O points. This is more than 5 times faster than any other fieldbus. SwiftNet minimizes and tightly controls timing jitter and the bad effects of bus overhead on synchronous scan