Device and method
A device includes a first interface unit connected to a first controller area network (CAN) bus, a second interface unit connected to a second CAN bus, and a control unit configured to identify, in a case where transmission of a CAN frame is started, a CAN bus detected to be in a dominant state first after end of arbitration from the first CAN bus or the second CAN bus, as a CAN bus to which a transmission source device of the CAN frame is connected.
1. A device comprising:
a first interface unit connected to a first controller area network (CAN) bus;
a second interface unit connected to a second CAN bus; and
a control unit configured to identify, in a case where transmission of a CAN frame is started, a CAN bus detected to be in a dominant state first after end of arbitration from the first CAN bus or the second CAN bus, as a CAN bus to which a transmission source device of the CAN frame is connected.
2. The device according to claim 1 , further comprising a connection unit configured to perform connection and disconnection between the first interface unit and the second interface unit, wherein
the control unit is configured to
output a connection instruction to the connection unit in a case where transmission of the CAN frame is started,
output a disconnection instruction to the connection unit in a case where end of the arbitration is detected, and
then output the connection instruction to the connection unit in a case where the dominant state of the first CAN bus or the second CAN bus is detected.
3. The device according to claim 1 , wherein the control unit is configured to detect end of the arbitration for the CAN frame based on lapse of a time length corresponding to 13 bits after detection of start of transmission of the CAN frame.
4. The device according to claim 2 , wherein, in a case where the first CAN bus or the second CAN bus that is identified as a CAN bus to which a transmission source device of a first CAN frame is connected is not registered as a legitimate CAN bus for transmission of the first CAN frame, the control unit is configured to outputs the disconnection instruction to the connection unit.
5. A method performed by a device connected to a first controller area network (CAN) bus and a second CAN bus, the method comprising:
detecting start of transmission of a CAN frame; and
identifying, in a case where transmission of the CAN frame is started, a CAN bus detected to be in a dominant state first after end of arbitration from the first CAN bus or the second CAN bus, as a CAN bus to which a transmission source device of the CAN frame is connected.