Bus network

About: Bus network is a research topic. Over the lifetime, 7017 publications have been published within this topic receiving 97556 citations.

Expansion bridge apparatus and method for an I2C bus

Abstract: The present invention is an I 2 C (inter-IC control) bridge device which implements a communication protocol layered on top of a standard I 2 C protocol. The layered protocol used by the bridge device is termed the “Layered I 2 C Protocol”—abbreviated “LIP”. Thus the bridge device is called a “LIP bridge device”. The LIP bridge device provides I 2 C address extension, data integrity checking, and fault detection and isolation when inserted between an I 2 C bus master and it's intended target I 2 C device. Each LIP bridge device has at least two attached I 2 C busses—a parent bus and a child bus. The LIP bridge operates as a slave on its parent bus, and a master of its child bus. The Layered I 2 C protocol is specified to operate on a bus between one or more bus masters and the parent bus of one or more LIP bridge devices. The child bus is used for attaching multiple I 2 C devices and/or one or more LIP bridge devices. In an exemplary implementation, the LIP bridge device is constructed using a microcontroller to create a LIP bridge device with one parent and one child I 2 C bus port and a group of LIP bridge configuration pins. The parent bus traffic to a given LIP bridge device consists entirely of LIP packets, and the child bus traffic consists of standard I 2 C packets to communicate with standard child bus I 2 C devices. The child bus traffic may also consist of LIP packets to communicate with LIP bridges attached to the child bus. By design, the LIP packets and standard I 2 C transactions do not interfere with one another. The LIP bridge device interprets LIP command packets from a bus master and translates them into the intended I 2 C data stream that is then broadcast over the child bus. Likewise, data from the child bus is used to create LIP packets that are returned to the proper bus master. The use of LIP packets on a given I 2 C bus provides an extra level of I 2 C addressing.

Bus allocation synchronization system

Abstract: An improved bus allocation system to control a time division multiplexed digital data bus used by a plurality of signal sources such as a number of digital processing components in a decentralized system in which there is no single entity controlling the bus. The system includes a mechanism for maintaining allocation synchronization under realistic, non-ideal conditions in which noise or other error producing interferences may be present. Each signal source is provided with a bus interface unit having an address counter which operates in conjunction with an allocation vector. The counters operate through a repeating cycle of counts and one or more of the counts in each cycle based on its allocation vector. Each address counter is synchronized during or following the receipt of a message using a unique comparison sequence of comparisons. By means of this system the value of all counters within the range of synchronization are made identical in response to a bus allocation synchronization signal. If a given address counter is off too many counts to be synchronized, the transmitter of the associated device is disabled until it can be re-synchronized by a later synchronization signal. Thus any device having a counter that is out of synchronization for any reason cannot transmit until such synchronization is restored. This prevents interference occasioned by more than one device using the bus at a given time.

Method and arrangement for transmitting data, especially in an aircraft

Abstract: A method and arrangement for the transmission of data, in digital form, in a bus system, which includes a central unit, several stations, as well as a bus line or data bus. During operation, the following different transmission phases take place: An initiation phase, in which the central control unit queries all of the stations and prepares a request phase; the request phase, in which the individual stations report a required bus access; an allocation phase, in which each station obtains a time slot in response to its request; and a data phase, for transmission of the data. The central unit includes a phase control, a request collector, a time slot allocator, and a register. A number of the stations are provided with a request generator in such a way that the latter can signal a need to the bus access. Thus, an optimum utilization of the transmission capacity is achieved, possibly by switching stations off. However, a rapid bus access is possible at any time for important stations.

Safety system for an elevator structure

Abstract: Disclosed is a safety system (10) for an elevator structure, comprising a control unit (11), a bus node (13), a safety element (16), and a bus (12) for enabling communication between the control unit (11) and the bus node (13). The bus node (13) is provided with first circuitry means (14) which impinge the safety element (16) with a first analog signal upon a digital input by the control unit (11). The bus node (13) is also provided with second circuitry means (15) which pick up an analog signal on the safety element (16) and supply digital feedback data to the control unit (11) via the bus (12).

Topology discovery in a hybrid network

Abstract: Systems and methods provide a discovery protocol allowing nodes that are interested in knowing a network topology to discover other nodes in the network topology. The discovery protocol includes two message types, topology discovery messages and topology query messages. A node issues topology discovery messages upon powering up, at periodic intervals, or upon detecting a change in network topology. The topology discovery messages are broadcast to all nodes on a network and identify the issuing node to the network. A topology query message is sent to a particular node and requests a response from the receiving node regarding the neighboring nodes of the receiving node. The querying node can use the response data to discover other nodes and to send the discovered nodes query messages such that the node can determine a network topology to a desired level of depth within the network.