摘要:
A multiplex transmission system, in which a node as a transmission node transmits data frame by frame to a transmission path, and a plurality of other nodes, as reception nodes, returns a reception acknowledgment signal to the transmission path upon proper reception of the frame of data. Each of the reception nodes which properly received the frame returns the reception acknowledgment signal specific thereto to that division of a reception acknowledgment signal area in the frame which corresponds to this node. Each node discriminates the success/failure of signal transmission, by comparing the information registered beforehand in its reception acknowledgment signal table with the information in the reception acknowledgment signal area. When the information of the reception acknowledgment signal table does not coincide with that of the reception acknowledgment signal area, the transmission node re-transmits the frame and the reception acknowledgment signal tables of all the nodes are updated. The system can not only effect the addition and deletion of multiplex nodes easily without requiring the change of scale of the circuit of the system, but also discriminate trouble for each of the multiplex nodes.
摘要:
A multiplex transmission system, in which a plurality of nodes are coupled together through a transmission path, and a node as a transmission node transmits a frame of data including a data area containing transmission data, to other nodes as reception nodes through the transmission path. The frame of data includes a data valid/invalid area having the same bit length as the data area and indicating, bit by bit, the validness/invalidness of the data carried by the corresponding bits in the data area. The system need not be modified depending on the model and grade of vehicles, and can be used widely and applied to various options by the use of a signal allocation system common to different models and grades of vehicles. Those bits in the data area which correspond to the bits in the data valid/invalid area indicative of data invalidness may have values thereof set to a fixed value, so that the reception node judges the transmission node to be defective when a bit of the data valid/invalid area of the received frame and the corresponding bit of the data area of the received frame make a combination of specific values.
摘要:
A multipath transmission system for an automobile according to the present invention comprises a plurality of multiplex transmission units connected in parallel with each other to one common bus. Each transmission unit is assigned to one of groups in which various devices attached to the automobile are classified. The transmission unit includes a sending circuit for transmitting the multiple signals from the devices in the group concerned to the other units through the bus. The system further comprises a power source for always applying electric power to the sending circuit of at least one of the multiplex transmission units. Only that multiplex transmission unit to which the electric power is always applied is provided with a bias circuit which sets the potential of the multiple signals on the bus when the multiple signals are supplied from the sending circuits of any multiplex transmission unit to the bus.
摘要:
A multiplex transmission system for automotive vehicles includes a plurality of communication nodes interconnected via a common multiplex transmission line. Each communication node includes a communication control device for controlling communication among the communication nodes in accordance with a decentralized multiplex protocol, a transmitting device for transmitting a reception acknowledgement signal to the multiplex transmission line upon receiving reception data from the multiplex transmission line normally in a reception mode, a memory device for storing beforehand, as data in table form, reception acknowledgment signals from respective ones of the communication nodes in a predetermined state, a comparator device for comparing, after a transmission, an actual reception acknowledgment signal from each communication node with the data table in a transmission mode, and a re-transmission control device for performing re-transmission control of communication among the communication nodes based on the results of the comparison.
摘要:
A multipath transmission system according to the present invention comprises a plurality of multiplex nodes connected to two multiplex buses. Each of the multiplex nodes is assigned to a specific apparatus, and includes a communication control circuit (LSI) for fetching multiplex signals from the apparatus and transmitting the multiplex signals to the multiplex buses. One multiplex node, out of the plurality of multiplex nodes, includes communication control circuits driver/receiver circuits, and troubleshooting driver/receiver circuits, which are connected to the multiplex buses and used for signal transfer between the buses, and a microprocessor for troubleshooting the multiplex buses and the multiplex nodes. The multiplex node relays a failure signal, corresponding to the result of troubleshooting, to the other network which suffers no trouble.
摘要:
A multiplex transmission system of this invention includes a plurality of multiplex nodes interconnected by a common multiplex transmission line. A frame of data is transmitted among the multiplex nodes through the multiplex transmission line. When a data frame transmitted from an air conditioner switch multiplex node (subnode) is received, an air conditioner unit multiplex node (main node), which is predetermined as a destination node, detects the contents of each data from an ID-a of the received data, performs a calculation on SOM to DATA 4 received, generates collation data (CRC) in accordance with the result of the calculation and transmits same. The subnode generates collation data (CRC), which is an error check code, through a calculation on the transmitted SOM to DATA 4, and compares the thus-generated CRC with the CRC received from the main node, to determine whether or not the data transmission was properly carried out. When the data transmission was carried out properly, the subnode returns a signal ACK3, and when the data transmission failed, the data frame is retransmitted, whereby the subnode need not have an ACK management function.
摘要:
A transmission failure diagnosis apparatus for use in a multiplex transmission system which sends and receives data by time division communication among a plurality of nodes connected by a common transmission path. This transmission failure diagnosis apparatus comprises a reception circuit, connected in the transmission path, for receiving a transmission signal on the transmission path, an amplitude detection circuit for detecting the signal amplitude of a transmission signal received by this reception circuit, and a judgment circuit for judging failures in the system on the basis of the amplitude of the transmission signal detected by the amplitude detection circuit.
摘要:
A device for controlling the current consumption of a power supply which applies a voltage to a transmission control circuit for transmitting a transmission signal with respect to a transmission line is provided. A power supply stabilizing circuit for stabilizing a voltage applied from the power supply; an amplitude detection circuit for detecting a transmission signal input from the transmission line; a switching circuit for interrupting application of a voltage from the power supply stabilizing circuit to the transmission control circuit; and a control circuit for controlling the open/closed state of the switching circuit according to the presence or absence of a transmission signal detected by the amplitude detection circuit are provided, and only when the amplitude detection circuit has detected the transmission signal, the control circuit sets the switching circuit into the closed state so as to permit a voltage to be applied to the transmission control circuit. When no transmission signal is transmitted, application of an unnecessary voltage to the transmission control circuit is interrupted, thereby reducing the current consumption.
摘要:
A multiplex transmission system includes a plurality of multiplex nodes interconnected by a common multiplex transmission line. Data frames are transmitted among the multiplex nodes through the multiplex transmission line. A data frame transmitted from a sending multiplex node includes a data area which is divided into subdivided areas in accordance with data transmitted therefrom and data transmitted from receiving multiplex nodes which send data in response to a send request, in accordance with the number of data pieces or the number of bits, and the receiving nodes send data to respective subdivided areas in a predetermined order, to thereby carry out a data transmission. Accordingly, the sending multiplex node can simultaneously collect data from the receiving multiplex nodes which are functionally subordinate. When any of the receiving multiplex nodes fails to return an ACK signal, the sending multiplex node retransmits the data frame.
摘要:
A solar battery system for a vehicle comprises a solar battery mounted on a body of the vehicle, a load connector for connecting selectively at least one of electric equipments provided in the vehicle with the solar battery so as to apply an output of the solar battery to the electric equipment connected thereby with the solar battery, a battery output checker for detecting the magnitude of the output of the solar battery, and a controller operative to select in response to the magnitude of the output of the solar battery detected by the battery output checker one or more of the electric equipments provided in the vehicle, which operate with power consumption corresponding appropriately to the output of the solar battery, as one or more electric equipments to be connected by the load connector with the solar battery.