Abstract: An electronic device includes a transceiver connected to a differential signal transmission line for transmitting a differential signal through a pair of signal lines to communicate with one or a plurality of other devices connected to the differential signal transmission line. The electronic device includes: a suppression circuit that is operated by a power source voltage to suppress waveform distortion in the differential signal transmitted through the differential signal transmission line; and a power source controller that controls supply or cutoff of the power source voltage to the suppression circuit in response to a change in a differential voltage between the pair of signal lines.

Abstract: A relay apparatus provided to a vehicle, performing first data communication with a first communication apparatus arranged outside the vehicle, and performing at least second data communication with multiple second communication apparatuses provided to the vehicle is provided. The relay apparatus includes a permission determination portion and an initiation switch portion. The permission determination portion determines whether first data communication between the first communication apparatus and a target second communication apparatus is permitted. The permission determination portion receives the first communication frame from the first communication apparatus through a connection switch portion determining a connection destination according to a control signal. The initiation switch portion outputs to the connection switch portion, the control signal designating the target second communication apparatus as the connection destination of the first communication apparatus.

Abstract: An information processing system made up of a plurality of controllers in a vehicle has a tamperproof configuration by including, in a specific controller among the plurality of controllers: a starter putting the specific controller among the plurality of controllers in a executable state which enables the specific controller among the plurality of controllers to execute a preset program; a determiner determining, before the specific controller among the plurality of controllers is put in the executable state, whether software that is memorized in a preset memory area and at least includes the preset program is tampered; and an outputter outputting, to one of processing devices outside the vehicle. In such manner, the tampering of the software is quickly detectable while preventing an increase of communication load of a communication network and/or the information processing system.

Abstract: A communication system is provide which includes a plurality of communication units connected to a communication line, in which collisions occur between dominant signals outputted from the communication units on the communication line. At least one of the communication units includes a first driver which is set so that a variation of voltage applied to the communication line in transmission of the dominant signal with respect to that in absence of transmission of the dominant signal is smaller than a variation of voltage applied from another of the communication units to the communication line in transmission of the dominant signal. One of the communication units, which differs from the communication unit including the first driver, includes a second driver which limits variation per unit time of current flowing through the communication line in transmission of the dominant signal.

Abstract: An electronic device includes a transceiver connected to a differential signal transmission line for transmitting a differential signal through a pair of signal lines to communicate with one or a plurality of other devices connected to the differential signal transmission line. The electronic device includes: a suppression circuit that is operated by a power source voltage to suppress waveform distortion in the differential signal transmitted through the differential signal transmission line; and a power source controller that controls supply or cutoff of the power source voltage to the suppression circuit in response to a change in a differential voltage between the pair of signal lines.

Abstract: A communications relay apparatus for relaying communications between an electronic control unit (ECU) connected to the apparatus via an in-vehicle local area network (LAN) and an external device connected to the apparatus via a communication path different from the in-vehicle LAN. In the apparatus, a data transfer unit forwards relay data received from the ECU to the communication path and forwards relay data received from the external device to the in-vehicle LAN. But the data transfer unit is inhibited from forwarding reprogramming data for reprogramming the ECU received from the external device to the in-vehicle LAN. An authentication unit authenticates a vehicle user, and when the vehicle user is successfully authenticated, then permits the data transfer unit to forward the reprogramming data to the in-vehicle LAN.

Abstract: A communication system operating with a battery is provided. Each node of the system is operable in a sleep mode and a normal mode, outputs a transition availability notice frame indicating whether or not the node is permitted or prohibited to transition to the sleep mode. At least one node is a monitor node. Upon receipt of a transition availability notice frame indicating prohibition of transition to the sleep mode while the battery is in a low voltage state, the monitor node stores sender information in a non-volatile memory, the sender information identifying what node is a sender node sending this transition availability notice frame.

Abstract: A delay system which has a communications device connected to a communications network and a relay device which is connected between the communications network ad an external device. The relay device is configured to divide data received from the external device into a plurality of data fragments each containing divided data, and send a sequence of messages, the messages corresponding to the respective divided data and dummy messages being included in the sequence of messages according to a communications rule. The communications device is configured to reconstitute the data from the external device on the basis of the message group from the relay device according to the communications rule.

Abstract: A relay apparatus provided to a vehicle, performing first data communication with a first communication apparatus arranged outside the vehicle, and performing at least second data communication with multiple second communication apparatuses provided to the vehicle is provided. The relay apparatus includes a permission determination portion and an initiation switch portion. The permission determination portion determines whether first data communication between the first communication apparatus and a target second communication apparatus is permitted. The permission determination portion receives the first communication frame from the first communication apparatus through a connection switch portion determining a connection destination according to a control signal. The initiation switch portion outputs to the connection switch portion, the control signal designating the target second communication apparatus as the connection destination of the first communication apparatus.

Abstract: Each of nodes in a communication system includes a pull-up circuit connected between a power source and a transmission line and a switching portion connecting and disconnecting the transmission line and a ground line. One of the nodes is a master node, and the others of the nodes are slave nodes. The driver circuits are driven so that the master node constantly outputs the transmission code of logic 1 and the slave node outputting the transmission code of logic 0 extends the width of the low level of the transmission code of logic 1 on the transmission line. The master node further includes a current limiting section limiting an electric current that flows to the transmission line via the pull-up circuit based on at least a signal level of the transmission line.

Abstract: A communication system performs communication using a pulse width modulation code as a transmission code. The communication system includes a plurality of nodes that are connected via a transmission line to be capable of communicating with each other. Each of the nodes including a driver circuit. The driver circuit includes a transistor that enables and blocks conduction between the transmission line and a ground line. The plurality of nodes includes a master node and a slave node. The master node is one of the plurality of nodes. The slave node is at least one node other than the master node among the plurality of nodes. The master node includes a limiter that restricts, when the transistor of the driver circuit is turned off, changes in a conductive state of the transistor.

Abstract: Each of nodes in a communication system includes a pull-up circuit connected between a power source and a transmission line and a switching portion connecting and disconnecting the transmission line and a ground line. One of the nodes is a master node, and the others of the nodes are slave nodes. The driver circuits are driven so that the master node constantly outputs the transmission code of logic 1 and the slave node outputting the transmission code of logic 0 extends the width of the low level of the transmission code of logic 1 on the transmission line. The master node further includes a current limiting section limiting an electric current that flows to the transmission line via the pull-up circuit based on at least a signal level of the transmission line.

Abstract: A communication system operating with a battery is provided. Each node of the system is operable in a sleep mode and a normal mode, outputs a transition availability notice frame indicating whether or not the node is permitted or prohibited to transition to the sleep mode. At least one node is a monitor node. Upon receipt of a transition availability notice frame indicating prohibition of transition to the sleep mode while the battery is in a low voltage state, the monitor node stores sender information in a non-volatile memory, the sender information identifying what node is a sender node sending this transition availability notice frame.

Abstract: A transceiver that transmits and receives data used in a communication system, in which the data is encoded by a transmission line code and a signal level of the transmission code changes at a predetermined transition timing in a bit-duration. The transceiver includes: a clock generator that generates an internal clock used for internal circuits; a timing generator that generates, by using the internal clock generated by the clock generator, a timing signal synchronized to a reference clock supplied externally; an encoding circuit that encodes, by using the timing signal generated by the timing generator, a transmission data which is synchronized to the reference clock to be the transmission line code; and a waveform shaping unit that performs a waveform shaping of a waveform at the predetermined transition timing of the transmission data to be based on the reference clock.

Abstract: A decoder for decoding an input signal coded with a pulse width modulation code as a line code to an output signal in a binary code, has a first memory, a first timer, a determination circuit and a first controller. The information on a duty duration of the PWM code, corresponding to at least one kind of the output signals, is stored on the first memory. The first timer has a capacity to measure the duty duration of the input signal. The determination circuit has a capacity to determining which kind of the output signals corresponds to the input signal, on the basis of the information stored on the first memory and the duty duration measured with the first timer. The first controller has a capacity to updating the information stored on the first memory, on the basis of the determination result and the measured duty duration.

Abstract: A communication apparatus includes a detecting unit, a process performing unit, and a range setting unit. The detecting unit detects a boundary pattern periodically appearing between codes in a binary coded signal transmitted through a transmission line. The boundary pattern is information showing a boundary appearing between codes. The process performing unit performs a process in synchronization with timing of appearance of the boundary pattern. The range setting unit sets an allowance range which is set include timing at which it is estimated that the next boundary pattern appears. The timing is counted from the timing currently detected by the detecting unit. The detecting unit includes a section which detects the timing of appearance of the boundary pattern during the allowance range.

Abstract: A communication system includes a plurality of nodes performing communication via a common communication channel based on a communication protocol and including a first node or a second node. The first node transmits, to the communication channel, a wake-up frame as the communication frame for enabling the second node to transition from a sleep state to a normal state, determines whether or not the second node transitions to the normal state due to the wake-up frame, and generates an abnormal waveform pattern in the communication channel when determined that the second node does not transition to the normal state. The second node stores the identification information allocated to the second node, and enables the second node to transition from the sleep state to the normal state under on condition that the identification information included in the wake-up frame received from the communication channel is identical to the stored identification information.

Abstract: A bus monitoring security device is connected to a bus, which includes a tool side bus having a tool connection terminal and an ECU side bus. The ECU side bus is coupled with an ECU, and the tool side bus is coupled with a tool capable of communicating with the ECU via the tool connection terminal. The tool side bus and the ECU side bus are separately coupled with the bus monitoring security device. The bus monitoring security device includes: a controller for determining whether the tool being to access the ECU is connected to the ECU side bus, and for restricting transmission and reception of data between the tool and the ECU when the controller determines that the tool is connected to the ECU side bus.

Abstract: An on-board network system is presented. The on-board network system sends a sleep-entered message to a communication bus. The sleep-entered message is sent under a condition that a sleep condition is satisfied on a basis that a network management (NM) message is ceased during state transition process in which node's state transfers from a normal state to a power-saving state. A monitoring ECU corresponding to a master performs an abnormality detection process. In the abnormality detection process, the monitoring ECU detects an abnormality state of the state transition process based on whether or not the sleep-entered message is sent from any one of nodes, thereby it is possible to detect the abnormality state not only during each node is a normal state but also during a bus-sleep state.

Abstract: A communication system performs communication using a pulse width modulation code as a transmission code. The communication system includes a plurality of nodes that are connected via a transmission line to be capable of communicating with each other. Each of the nodes including a driver circuit. The driver circuit includes a transistor that enables and blocks conduction between the transmission line and a ground line. The plurality of nodes includes a master node and a slave node. The master node is one of the plurality of nodes. The slave node is at least one node other than the master node among the plurality of nodes. The master node includes a limiter that restricts, when the transistor of the driver circuit is turned off, changes in a conductive state of the transistor.