Denso Corporation

Nippon Soken, Inc.

So-ken Corporation

Nippondenso Co., Ltd.

Toyota Jidosha Kabushiki Kaisha

Anden Co., Ltd.

Tomohisa Kishigami

Hiroyuki Mori

Hideki Kashima

Hirofumi Isomura

Takuya Honda

Naoji Kaneko

Hajime Kikkawa

Youichirou Suzuki

Noboru Maeda

Shinichi Senoo

Masakiyo Horie

Nobutomo Takagi

Akihiro Sasaki

Akihiro Tanaka

Hiroyuki Obata

Hiroshi Honda

Jiro Sato

Takahisa Koyasu

Tomoyuki Koike

Youhei Sekiya

Kazunori Sakai

Masato Kume

Tomoko Kodama

Tomoya Tokunaga

Shigeru Uehara

Hajime Mikuni

Noriyoshi Ando

Tetsuo Nakagawa

Yasushi Shinojima

Kouji Fujiki

Yoshinori Takai

Yasumasa Imai

Shuichi Nakamura

Satoshi Suzuki

Yuzo Harata

Shigeki Takahashi

Yoshihisa Sato

Mitsuyoshi Natsume

Hironobu Akita

Akira Tada

Masachika Kamiya

Kazuyoshi Nagase

Ikuo Hayashi

Michinaga Nagura

Keiji Shigeoka

Masayoshi Satake

Kazuhisa Ishimaru

Toshihiro Wakamatsu

Nobuaki Matsudaira

Kenji Tomita

Yasushi Kanda

Yasuhiro Fukagawa

Mitsutoshi Kato

Yasuyuki Takahashi

Masahiro Kitagawa

Shigeki Ohtsuka

Naoya Tsuchiya

Masakazu Doi

Katsuhisa Tsuji

Ken Aida

Takahiro Sasaki

Naoki Kamikawa

Katsuhiko Furuta

Yuki Horii

Mikito Yagyu

Hisashi Miyoshi

Hiroki Suzuki

Yoshiki Tatsutomi

Mitsuru Matsunaga

Naoki Horie

Yasuhiro Mori

Aya Yoshimura

Keiichi Yoshino

Kunimitsu Handa

A network system includes at least one transmission path and a plurality of terminal devices each connected to the transmission path. Each of the terminal devices includes a transceiver, a startup processing unit, and a switching unit. The transceiver is configured to operate either one of a first standby unit and a second standby unit according to a switching instruction. The switching unit is configured to output the switching instruction to the transceiver to operate the second standby unit when a transmission path empty period lasts for a predetermined preparation time or more after a non-designation period has lasted for a predetermined operation determination time or more.

Network system

A relay device relays a management frame between nodes connected to mutually different communication buses. The relay device includes (i) communicator units provided respectively to correspond to the communication buses, and (ii) communication controller units provided respectively to correspond to the communicator units. The communication controller unit respectively includes a corresponding transmission buffer configured to store the management frame, which is to be transmitted from the communicator unit corresponding to the communication controller unit. In response to determining that the management frame is retained in the transmission buffer corresponding to the communication controller unit, the communication controller unit transmits the management frame, which is received at a present time and stored in the transmission buffer, from the communicator unit corresponding to the communication controller unit.

Relay device

A relay device in a communication system receives a plurality of wakeup frames from one or more than one communication device connected to each bus of a plurality of buses via a corresponding port. The relay device obtains an aggregated wakeup pattern by aggregating information on an operating mode of each communication device included in the plurality of wakeup frames so as to include predetermined information to be transmitted and received and reduce the number of wakeup patterns. By using the aggregated wakeup pattern obtained by aggregating the information on the operating mode, a wakeup frame for transmission to each bus via the corresponding port is prepared.

A communication system, in which a plurality of nodes communicate with each other according to a communication protocol, which wakes up some of the plurality of nodes when a communication frame containing specific start information occurs on or is transmitted to the communication bus, includes a master node determines, for each of slave nodes, a start condition, which is a condition for transition of a subject node from a sleep state to a normal state. The master node transmits, to the communication bus, the determined start condition tailored for each of the slave nodes for a reception thereof by each of the slave nodes.

Communication system

A PoE power supply system includes a cable, a power supply device, a power reception device, and a request switch. The power supply device includes a power supply block and a power supply control block. The power supply block is configured to enable a connection state between the power supply device and the cable to be switched. The connection state includes a power supply state in which the power supply device is supplied with power required for operating the power supply device via the cable, and a standby state in which the power supply request signal is receivable by the power supply device via the cable. The power supply control block is configured to switch the connection state to the power supply state in response to receiving a power supply request signal output from the request switch and requesting the power supply device to resume supplying the power.

POE power supply system

A ringing suppressor circuit is connected to a differential signal transmission line that includes a high potential signal line and low potential signal line pair for transmitting high and low level differential signals, and includes a ringing suppressor and a stopper. When the differential signal changes to a high level, the ringing suppressor suppresses ringing by lowering the impedance between the signal lines by turning ON of a switching element. When a differential signal voltage drops below a voltage lowering determination voltage, the stopper stops the impedance lowering function of the ringing suppressor by turning OFF another switching element.

Ringing suppressor circuit

A ringing suppression circuit is provided at one or more nodes each having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines connected to the nodes. The circuit includes a suppression circuit and an operation mode controller: The suppression circuit is configured to execute a suppression operation for suppressing ringing in the differential signal. The operation mode controller is configured to set an operation mode of the suppression circuit to one of: a normal operation mode, which enables the suppression circuit to execute the suppression operation in response to detecting a change in a level of the differential signal, and a permanent off mode, which disables the suppression circuit to execute the suppression operation on a steady basis.

Ringing suppression circuit

An electronic control unit coupled to a transmission line of a differential signal includes: a first suppression circuit suppressing a ringing effect and decreasing an impedance of the line for a first time interval when a level of the differential signal changes; a second suppression circuits suppressing a ringing effect and decreasing the impedance of the line for a second time interval when the level of the differential signal changes; and a switching unit isolating the second suppression circuit from the line when the operation power source energizes the electronic control unit, and connecting the second suppression circuit to the line when the operation power source does not energize the electronic control unit.

Electronic control unit

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.

Information processing system

A ringing suppression circuit connected to a transmission line to suppress ringing caused by the transmission line transmitting a differential signal using a pair of signal lines, the differential signal varying between a high level and a low level, the pair of signal lines including a high potential signal line and a low potential signal line, the ringing suppression circuit including: an inter-line switching element that is connected between the pair of signal lines; a control portion that performs a ringing suppression operation in response to detecting a level change in the differential signal, wherein the ringing suppression operation turns on the inter-line switching element to decrease an impedance between the pair of signal lines; and a suppression operation prohibiting portion that prohibits the control portion from performing the ringing suppression operation in response to detecting a signal caused by a signal on the transmission line.

Ringing suppression circuit and ringing suppression method

A ringing suppression circuit is provided at a node having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines. The ringing suppression circuit includes: a suppressor configured to perform a suppression operation to suppress ringing occurred with a transmission of the differential signal by connecting a resistive component between the pair of communication lines; and a reference potential provider configured to provide a reference potential, which corresponds to a midpoint potential of the pair of communication lines during a steady state, to an intermediate point of the resistive component.

In a communication device, when an enabling signal is at a high level and a transmit data is at a high level, that is, in a recessive period, both transistors turn off. Thus, potentials of signal lines are determined by power supply from a second transmitting part to a communications network. When an error frame arises in this state, that is, transistors in the other ECU turn on, excessive currents flow the signal lines. When current monitoring circuits detect error currents, an error signal is changed to a high level.

Communications device for transmitting a differential signal

A transmission circuit includes a first transmitter and a second transmitter. The first transmitter turns OFF first transistors when a transmission data is in a high level, and turns ON the first transistors when the transmission data is in a low level. When a permission signal is in the high level, the second transmitter turns ON the second transistors when the transmission data is in the high level, and turns OFF the second transistors when the transmission data is in the low level. Diodes are set to suppress an amplitude of a differential signal in an ON time of the second transistors more than an amplitude of a differential signal in an ON time of the first transistors, to suppress ringing and radiation noise.

Transmission circuit

A communication system includes a transmission path and multiple nodes. At least one of the multiple nodes includes a second communication portion and a control portion in addition to a first communication portion. When the control portion performs a high speed communication, the control portion shifts the first communication portion included in each of the remaining multiple nodes to a sleep mode. The second communication portion performs a differential communication at a higher speed than the first communication portion using a differential signal. In the differential signal, a maximum of a potential difference between the pair of communication lines is equal to or less than a recessive threshold value, and a minimum of the potential difference between the pair of communication lines is a negative voltage value that has a polarity opposite to the recessive threshold value of the first communication portion.

A communication load determining apparatus is used for a communication system which includes a plurality of communication devices performing communication via a common bus. The communication system operates in accordance with a communication protocol that defines which a priority order is set to each of the frames transmitted from the communication devices and which a frame having a lower priority has a longer transmission latency before being transmitted to the bus. In the communication load determining apparatus, a low-priority frame having a lower priority than other frames to the bus is transmitted, and a transmission latency of the low-priority frame is measured. The communication load determining apparatus determines whether or not abnormality has occurred in a communication load in the bus on the basis of the measured transmission latency to produce a determination result. The produced determination result is stored.

Communication load determining apparatus

Growing community of inventors

Obu, Japan

Tomohisa Kishigami