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MIL-STD-1553 has served the needs of military system integrators for over 30 years, particularly in the area of command and control applications. Nevertheless, contemporary applications such as high-speed digitized sensors, file transfers, processor clusters, and displays require much higher data rates than 1553's 1 Mb/s. For some environments, particularly for legacy aircraft, the optimal solution is to transmit faster data rates over existing 1553 buses. However, there are other applications that can accommodate and benefit by the deployment of gigabit or multi-gigabit copper or optical switched fabric networks. In addition to MIL-STD-1553, this paper presents and comments about several avionics networking technologies including High-Speed 1553, Fibre Channel, Gigabit Ethernet, and ARINC 664, a form of profiled Ethernet.

Time Triggered networking technologies such as TTP (Time Triggered Protocol) are beginning to be used in critical aerospace applications such as flight controls. While TTP provides stringent specifications for determinism and fault tolerance, it does not define a physical layer. TTP's “de facto” physical layer, RS-485, includes shortcomings in a number of areas. These include a relatively low minimum transmitter voltage, low receiver threshold, along with a lack of specificity in a number of areas. The latter include bus signal levels, transmitter zero-crossing distortion and receiver zero-crossing tolerance, isolation method, terminal output noise, common mode and noise rejection, and input impedance. MIL-STD-1553, which has been deployed in flight and mission critical military applications for decades, defines a highly proven and robust physical layer. This paper presents MIL-STD-1553's physical layer as a candidate for use with TTP.

System requirements and Interface Control Drawings (ICDs) make a variety of demands for MIL-STD-1553 remote terminals (RTs). Among these requirements are the need to ensure data integrity and sample data consistency, the need to perform bulk (multi-message) data transfers, and the need to offload the operation of the host CPU to the greatest degree possible. This latter requirement is reflected in such specifications as CPU spare bandwidth. The latest 1553 terminals provide a variety of choices for performing the different types of transfers. This paper provides a discussion of the hardware and software techniques for achieving these objectives. Three different schemes for RT subaddress memory management are presented: single message, circular buffer, and double buffered. For receive and transmit messages, these include fully synchronous single message transfers, asynchronous single message transfers, and multi-message transfers.