Abstract: A vehicle-mounted control device, which communicates with a vehicle-mounted node via a common bus and follows a communication protocol that the lower the priority of a data frame output from the vehicle-mounted node, the longer a waiting time, includes: an arbitration device that suspends transmission of the transmission target frame to the bus when the priority of a transmission target frame is lower than an output data frame from the vehicle-mounted node, and continues transmission of the transmission target frame to the bus when the priority of the transmission target frame is higher than the output data frame; and a change device that changes the priority of the transmission target frame to be the highest of all data frames when the transmission of the transmission target frame is suspended for a prescribed time or longer as a result of arbitration control by the arbitration device.

Abstract: A vehicle-mounted control device, which communicates with a vehicle-mounted node via a common bus and follows a communication protocol that the lower the priority of a data frame output from the vehicle-mounted node, the longer a waiting time, includes: an arbitration device that suspends transmission of the transmission target frame to the bus when the priority of a transmission target frame is lower than an output data frame from the vehicle-mounted node, and continues transmission of the transmission target frame to the bus when the priority of the transmission target frame is higher than the output data frame; and a change device that changes the priority of the transmission target frame to be the highest of all data frames when the transmission of the transmission target frame is suspended for a prescribed time or longer as a result of arbitration control by the arbitration device.

Abstract: An in-vehicle system comprising a gateway between multiple networks is disclosed. One of the networks specifies that when a source apparatus connected to the one of the networks sends a request message to a destination apparatus connected to another one of the networks, the source apparatus should time-out if the source apparatus does not receive a response message within a specified time after sending the request message. Upon receipt of the request message, the gateway relays the request message to the destination apparatus and sends a wait request code to the source apparatus to instruct the source apparatus to wait by extending the specified time.

Abstract: A gateway apparatus performs frame forwarding between an external device connected to a first bus and controllers connected to a second bus. Each controller outputs a response frame upon reception of a communication frame from the external device. The response frame has an address field in which a private address is set. The private address is uniquely assigned to each controller in a private network space defined by the second bus. When the communication frame is directed to each controller, the communication frame is forwarded to each controller in sequence at different times to prevent collision between the response frames in the second bus. The private address set in the address field of the response frame is converted into a predetermined transmitting address specified in the first bus.

Abstract: An in-vehicle system comprising a gateway between multiple networks is disclosed. One of the networks specifies that when a source apparatus connected to the one of the networks sends a request message to a destination apparatus connected to another one of the networks, the source apparatus should time-out if the source apparatus does not receive a response message within a specified time after sending the request message. Upon receipt of the request message, the gateway relays the request message to the destination apparatus and sends a wait request code to the source apparatus to instruct the source apparatus to wait by extending the specified time.

Abstract: A gateway apparatus performs frame forwarding between an external device connected to a first bus and controllers connected to a second bus. Each controller outputs a response frame upon reception of a communication frame from the external device. The response frame has an address field in which a private address is set. The private address is uniquely assigned to each controller in a private network space defined by the second bus. When the communication frame is directed to each controller, the communication frame is forwarded to each controller in sequence at different times to prevent collision between the response frames in the second bus. The private address set in the address field of the response frame is converted into a predetermined transmitting address specified in the first bus.