Patent ID: 11962433
Assignee: AUTONETWORKS TECHNOLOGIES, LTD.
Field: Digital communication (Electrical engineering)
Classification: CPC H  B | IPC B  H

Claim 12:
13. A communication method for an in-vehicle communication system that includes a plurality of switch devices and is used in a vehicle in which a plurality of function units and a diagnosis device are installed,
each switch device including a plurality of communication ports,
each switch device relaying a frame, which has been transmitted from a function unit and to which information including an ID of a \IAN is added, to another function unit,
the method comprising:
when the diagnosis device is connected to another switch device, causing a first switch device to
determine that the frame is to be duplicated based on at least a source address and a destination address included in the frame,
duplicate the frame to be relayed via a designated communication port among the plurality of communication ports,
generate a duplicate frame for diagnosis that is a frame obtained by adding, to a duplicate frame obtained through the duplication, specific information indicating that the duplicate frame for diagnosis should be transmitted to the diagnosis device, and
output the generated duplicate frame for diagnosis from a communication port corresponding to the other switch device;

when the specific information is added to the frame received from the other switch device, causing a second switch device to determine that the received frame is the duplicate frame for diagnosis and to set, to ON, a diagnosis flag of the frame that has been determined as the duplicate frame for diagnosis; and
when the diagnosis flag is ON, causing the second switch device to output the duplicate frame for diagnosis from a communication port corresponding to the diagnosis device among the plurality of communication ports.