Abstract: The invention refers to a method for monitoring a communication media access schedule of a communication controller (5) of a communication system (1) by means of a bus guardian (6). The communication system (1) comprises a communication media (2) and nodes (3) connected to the communication media (2). Each node (3) comprises a communication controller (5) and a bus guardian (6) assigned to the communication controller (5). Messages are transmitted among the nodes (3) across the communication media (2) based on a cyclic time triggered communication media access scheme.

Abstract: The invention concerns a network comprising an interconnecting network and several network nodes that are coupled to said interconnecting network and are designed to adapt their local communication time schedule to the communication time schedule of at least one other network mode, prior to being integrated as active network nodes. A network node to be integrated checks the activity of other network nodes and if no activity is identified, sends out positional messages for other network nodes, said message being fixed by predetermination in its communication time schedule. If a network node cannot be integrated as a reference node, it can only be integrated as an active node if it adapts its local communication time schedule to that of the reference node after receiving positional messages and if a check as to whether its own communication time schedule agrees with the communication time schedules of at least some of the active network nodes proves positive.

Abstract: An apparatus and method for detecting optical defects in optical bus systems which use optical modules in communication with a plurality of nodes connected to each other. Deterioration of the optical transmission quality is detected as a resulting deterioration in an electrical output signal and noted deterioration is stored and read out.

Abstract: A method and a bit stream decoding unit for bit stream decoding has a bit stream comprising a number of consecutive samples. In order to provide for rapid and, in particular, reliable decoding of the bit stream, a detection window comprising a number of samples is defined and the detection window is positioned at certain positions on the bit stream in order to comprise certain samples with respective sample values. A majority voting is applied to the sample values in the detection window and, in dependence on the result of the majority voting, the bit stream is decoded and respective bit values are generated.

Abstract: The invention concerns a network comprising an interconnecting network and several network nodes that are coupled to said interconnecting network and are designed to adapt their local communication time schedule to the communication time schedule of at least one other network mode, prior to being integrated as active network nodes. A network node to be integrated checks the activity of other network nodes and if no activity is identified, sends out positional messages for other network nodes, said message being fixed by predetermination in its communication time schedule. If a network node cannot be integrated as a reference node, it can only be integrated as an active node if it adapts its local communication time schedule to that of the reference node after receiving positional messages and if a check as to whether its own communication time schedule agrees with the communication time schedules of at least some of the active network nodes proves positive.

Abstract: The invention relates to an operating method for a data bus for several parties with flexible, timed access. According to the method, the parties are synchronized, the bus messages are sent from the parties in a hierarchical sequence and are sent at least in part, only if necessary. A logic element is provided between the parties and the data bus which only gives bus access to each party when said party is allowed to send and for the duration of the send operation.

Abstract: The invention refers to one of a number of nodes of a communication system. The nodes are connected to a communication media for transmitting data among the nodes. Said one node comprises a communication controller, across which the node is connected to the communication media, and a bus guardian for controlling access of the communication controller to the communication media. In order to provide a cheap but nevertheless reliable way for monitoring the synchronized clock signal of a node of a communication system and in particular for detecting deviations of the synchronized clock signal it is suggested that a synchronized clock signal from the communication controller is made available to the bus guardian, and that the bus guardian comprises means for monitoring the synchronized clock signal using a bus guardian internal clock signal, which is generated by means of an electronic circuit and which is less accurate than the synchronized clock signal to be monitored.

Abstract: In the case of a data bus for several users, the users have hierarchical transmission authorizations; the users are synchronized by a synchronization signal; and the communication of the user with the highest priority, which can be emitted at regular time intervals by this user, serves as a synchronization signal.

Abstract: An arrangement for exchanging data among a plurality of nodes by providing a logical decision gate wherein inputs of the logical decision gate are providing with converted node output signal and wherein the output of the logical decision gate provides signals to each of said nodes through a respective signal converter. The signal converter outputs electrical signals to said logical decision gate.

Abstract: A data bus arrangement for a plurality of nodes connected to each other including a logical decision gate having a plurality of inputs corresponding to the number of nodes. A converter module is connected between each node and the logical decision gate. Each convertor module converts an optical output from one of the nodes to an electrical signal which is fed to one of the inputs of the logical decision gate. A separate switch is connected between an output of the logical decision gate and an input of each one of said convertor modules for controlling the convertor module independent of an output signal on the output of the decision gate.

Abstract: A data bus arrangement and method for connecting a plurality of nodes to one another through a star coupler arrangement of a data bus which uses a logical decision gate having a plurality of inputs corresponding to said plurality of nodes wherein the logical decision gate inputs receive electrical signals and outputs an electrical signal to be routed back to each of said plurality of nodes. Some of the nodes are connected through opt0-electric transducers to the inputs of the logical decision gate. These transducers convert optical input signals from the nodes to electric signals to the inputs of the logical decision gate and also convert the output from the logical decision gate back to optical signals to the nodes. A signal conditioning circuit modifies the output signal of the logical decision gate.

Abstract: A data bus structure for cooperating with a plurality of nodes which are connected to each other. The data bus structure includes optical transmission modules associated with each node and a logical decision gate having inputs associated with each node. The logical decision output signal is provided in parallel to each node through the optical transmission modules. These modules serve to convert optical signals from the nodes to electrical signals and output to the logical decision gate and to convert electrical signals output from the logical decision gate to optical signals and output to the nodes. In order to separate a single node from the data bus, the transmission mode is monitored and an independently controlled switch is positioned between the logical decision gate and the optical transmission module. This arrangement functions to exclude a node from bus communication while leaving the remaining nodes uninterrupted.

Abstract: A method and a bit stream decoding unit for bit stream decoding has a bit stream comprising a number of consecutive samples. In order to provide for rapid and, in particular, reliable decoding of the bit stream, a detection window comprising a number of samples is defined and the detection window is positioned at certain positions on the bit stream in order to comprise certain samples with respective sample values. A majority voting is applied to the sample values in the detection window and, in dependence on the result of the majority voting, the bit stream is decoded and respective bit values are generated.

Abstract: Method for transmitting data within a communication system, the communication system comprising a communication media and a number of nodes connected to the communication media, the data being transmitted across the communication media within a communication cycle comprising a number of time slots assigned to one or more nodes of the communication system. In order to provide a possibility for a data transmission within communication cycles, which can satisfy the demands in communication systems for safety critical applications, too, it is suggested, that the communication cycle is initiated by an external event. The external event can be caused by manually setting a bit by a host, by a configurable timer in a controller host interface (CHI) or by an external trigger.

Abstract: The invention refers to a method for monitoring a communication media access schedule of a communication controller (5) of a communication system (1) by means of a bus guardian (6). The communication system (1) comprises a communication media (2) and nodes (3) connected to the communication media (2). Each node (3) comprises a communication controller (5) and a bus guardian (6) assigned to the communication controller (5). Messages are transmitted among the nodes (3) across the communication media (2) based on a cyclic time triggered communication media access scheme.

Abstract: A data bus arrangement and method whereby a plurality of nodes are connected to each other through a star coupler arrangement of a data bus. The data bus arrangement includes a logical decision gate which received a plurality of input electrical signals transmitted from a plurality of nodes with some of the signals being transmitted through an opto-electrical transducer to convert optical node signals to electrical signals output to the logical decision gate. The output of the logical decision gate is connected to each of the nodes with at least some of the nodes being connected through respected opto-electrical transducer to convert the electrical output signal from the respective logical decision gate to an optical signal fed to the nodes. In order to adjust the output signal from the logical decision gate, a signal preparation circuit provides pulse form adjustment in order to correspond to electrical input signals which enter the logical decision gate.

Abstract: A data bus for establishing a connection among a plurality of nodes and having configuration whereby optical data messages are converted to an electrical signal and sent through a logical decision gate to each of the nodes. A memory element, which is connected in parallel to the input of the logic decision gate, provides an addressable manner of monitoring data traffic on the data bus and identifying a source of any malfunction.

Abstract: The invention relates to a method for securing data transfer in a data bus via which data telegrams of at least one transmitter are transferred containing a data field of a variable length and a check sum and the data transfer quality is determined by the receiver using the check sum, said check having a shorter length when the data field length is shorter than when the data field is longer.

Abstract: The invention relates to an operating method for a data bus which is provided with a clock generator. A second clock generator is activated when said first clock generator has a failure.

Abstract: The invention relates to an operating method for two data buses, each with a clock generator. The clock generators are synchronized with one another, by the clock generator of the higher frequency synchronizing the clock generator of the lower frequency to its own clock pulse frequency.