A communication control device includes a frame configuration section configured to reconfigure a frame by changing a ratio of each of data partitions in a data field according to a communication state of a network including multiple nodes, and a process command section configured to instruct the multiple nodes to execute configuration process such that the multiple nodes are enabled to transmit and receive the reconfigured frame.

A method for operating a data bus subscriber of a local bus, particularly of a ring bus, the method including the steps of: receiving a first data packet over the local bus, wherein the first data packet has an address of the data bus subscriber to which it is directed and at least one instructions list, having a set of instructions for processing process data, receiving a second data packet over the local bus, wherein the second data packet has process data; and executing instructions of the at least one instructions list for processing the received process data. A corresponding data bus subscriber and a local bus master is also provided.

A method for operating a data bus subscriber of a local bus, particularly of a ring bus, the method including the steps of: receiving a first data packet over the local bus, wherein the first data packet has an address of the data bus subscriber to which it is directed and at least one instructions list, having a set of instructions for processing process data, receiving a second data packet over the local bus, wherein the second data packet has process data; and executing instructions of the at least one instructions list for processing the received process data. A corresponding data bus subscriber and a local bus master is also provided.

An elevator system has a central control unit for generating control signals and/or processing sensor signals and controlling functions of the system, a plurality of field devices distributed inside a structure accommodating the system, preferably along an elevator shaft, and a field bus system for interchanging the signals between the control unit and the field devices. Each field device outputs sensor signals generated by a sensor and/or receives control signals to be implemented by an actuator. Data packets including the signals are interchanged in a serial manner between the control unit and all field devices in a summation frame method using a closed ring topology. Each field device has a driver to insert the sensor signals into the data packet or to remove the control signals from the data packet. Data and signal transmission is thereby carried out quickly and safely in a safety circuit of the elevator system.

An elevator system has a central control unit for generating control signals and/or processing sensor signals and controlling functions of the system, a plurality of field devices distributed inside a structure accommodating the system, preferably along an elevator shaft, and a field bus system for interchanging the signals between the control unit and the field devices. Each field device outputs sensor signals generated by a sensor and/or receives control signals to be implemented by an actuator. Data packets including the signals are interchanged in a serial manner between the control unit and all field devices in a summation frame method using a closed ring topology. Each field device has a driver to insert the sensor signals into the data packet or to remove the control signals from the data packet. Data and signal transmission is thereby carried out quickly and safely in a safety circuit of the elevator system.

An apparatus and method for operating a ring interconnect are disclosed. The ring interconnect has a plurality of nodes that are used to connect to associated components, and is arranged to transport a plurality of slots around the ring interconnect between the nodes in order to transfer items of traffic allocated into those slots between components connected to the nodes. For each item of traffic, one of the components acts as a source to allocate that item of traffic into a slot, and another components acts as destination to seek to remove that item of traffic from the slot. In a default mode of operation, the ring interconnect is arranged to allow all of the slots to be available for transfer of any items of traffic. Special slot management circuitry is provided that is responsive to a throughput alert trigger indicating a potential for occurrence of a throughput inhibiting condition, to cause a slot amongst the plurality of slots to be reserved as a special slot that is constrained for use only when one or more determined conditions are met. Further, the one or more determined conditions are arranged to cause the special slot to be used in a manner that seeks to avoid the throughput inhibiting condition arising.

Multiple nodes (2) of a ring network communication system (1) include a heteronomous node (22) and an autonomous node (23). The heteronomous node (22) operates in a heteronomous mode in which data generated by a data generation part (8) of an own node is transmitted as transmitted data Dt only when received data Dir received by a data reception part (13) includes a data transmission request. The autonomous node (23) operates in an autonomous mode in which the data generated by the data generation part (8) of the own node is transmitted as the transmitted data Dt regardless of reception of the received data Dir including the data transmission request. Data including the data transmission request is not required for the autonomous node, and the control period is shortened.

A method is described for identifying communication-ready data bus subscribers connected to a local bus. The method comprises receiving, at a local bus master, at least one data packet transmitted via the local bus, wherein the at least one data packet received at the local bus master comprises an address of a communication-ready data bus subscriber among a plurality of communication-ready data bus subscribers in the local bus, wherein the communication-ready data bus subscriber is in a sequence of communication-ready data bus subscribers, and mapping of the received address by the local bus master to a relative position of the communication-ready data bus subscriber in the sequence of communication-ready data bus subscribers in the local bus. In addition, a local bus master of the local bus is described.

A method is described for identifying communication-ready data bus subscribers connected to a local bus. The method comprises receiving, at a local bus master, at least one data packet transmitted via the local bus, wherein the at least one data packet received at the local bus master comprises an address of a communication-ready data bus subscriber among a plurality of communication-ready data bus subscribers in the local bus, wherein the communication-ready data bus subscriber is in a sequence of communication-ready data bus subscribers, and mapping of the received address by the local bus master to a relative position of the communication-ready data bus subscriber in the sequence of communication-ready data bus subscribers in the local bus. In addition, a local bus master of the local bus is described.

An object of the present invention is to provide a communication system and a communication method that can suppress an increase in the total fiber distance even if the number of secondary devices increases and that can make complex processing for band allocation for uplink optical signals unnecessary. The configuration of the communication system according to the present invention is a mixture of a ring type and a branch type, in which an optical fiber cable (primary path) from a communication station to each user's home is arranged in a ring (loop) shape, and the primary path is branched and laid to the user's home. Furthermore, unidirectional communication is enabled by a ring-type primary path, and the transmittable amount can be made uniform by further combining time division multiplexing.