Patent ID: 7337245

Claim:
A protocol adapter for transferring diagnostic messages between a vehicle network in a vehicle and an external host computer, said adapter comprising: a control area network (CAN) transceiver circuit, said CAN transceiver circuit providing an interface between the vehicle network and the host computer when the vehicle network is operating in a J1939 protocol; a J1708 transceiver circuit, said J1708 transceiver circuit providing an interface between the vehicle network and the host computer when the vehicle network is operating in a J1708 protocol, said J1708 transceiver circuit including a voltage translator for translating the voltage of the J1708 protocol signals; and a central processing unit (CPU), said CPU controlling the operation of the CAN transceiver circuit and the J1708 transceiver circuit to switch between the CAN transceiver circuit and the J1708 transceiver circuit depending on whether the host computer is operating in the J1939 protocol or the J1708 protocol or both.