Digital Systems Validation Handbook. Volume 2. Chapter 18. Avionic Data BusIntegration Technology

摘要

As multiple digital avionic systems were introduced into aircraft, there arose aneed for digital communications between systems. In the early 1970's, many different digital data bus designs were used to provide this communication. Because these digital systems proved to be reliable and cost effective, their popularity increased. Proliferation led to standardization, particularly in the air transport category of aircraft, which allowed communications between line replaceable units (LRUs) to become more complex. The LRUs began to rely more heavily on each other to reduce the amount of equipment required. Sensor data and systems data could be shared among multiple systems, rather than each system requiring its own private source. Integrated digital avionics are increasingly being used to implement essential and critical functions that cannot be sufficiently reproduced by conventional means. The safety of such aircraft is highly dependent upon the computer software, hardware, and data buses connecting the systems. The newest concerns relate to the problems that are unique to highly integrated systems. There is no standard with which to assess the possible impact of these bus-based systems on aircraft safety. These and other advanced avionic systems will result in specific safety assessment problems when the appropriate data packages are submitted to the Federal Aviation Administration during the certification process. Avionics, Data bus, Integration, Buffer, Controller, Network, Protocol, Digital, Software, Error, Fault, Frame, Interrupt, Parity, Station, Token, Multiplexing.