Abstract: The present invention governs the order of destination nodes to which each node will send by establishing an individual circular output routing scheme for each node based on that node's unique identifier, thereby evenly distributing node traffic. The output routing scheme for each node can begin with the next incrementally higher node identifier. The output routing scheme can be built by incrementing the node identifiers until the highest node identifier is reached. The lowest node identifier follows the highest node identifier. Then, the node identifiers are again incremented until the sending node's identifier is reached. Each node can iteratively follow its own output routing scheme.

Abstract: A modular control system for a railroad classification yard is described. The control system can automatically perform those functions necessary to control the various elements of a railroad classification yard to enable the train of cars to be switched from a hump track to one of a plurality of bowl tracks in accordance with the destination for the car. The control system comprises a number of subsystems including a hump control system (HUMPCON), an operator communications subsystem (OPCOM), a switching control subsystem (MASC), a retarder control subsystem (MARC), a multidrop communications system (MDCOM), a crest monitor subsystem (CMON) and a distance to couple subsystem (MADTC). Some of the subsystems are implemented as singular modules (HCON, OPCOM, CMON). Other subsystems include multiple modules (MARC, MASC, MDCOM). Each module in each subsystem is comprised of a single microprocessor and related peripheral circuits.