IEI Industrial Partner

IEI IKARPC - Vehicle Computer Simple Type: System

Vehicle Bus Protocol (OBD-II/J1939/FMS). A vehicle bus protocol is a specialized internal communications network that interconnects components inside a vehicle. It also provides interface for users to acquire vehicle data for diagnostic or travel information such as vehicle speed, engine loading, engine R.P.M and fuel level. For example, OBD-II supports more than 79 kinds of vehicle information. The vehicle bus protocol deals with special request for data transmision reliability and quality on vehicle bus. The MCU inside iKarPC acts as a converter among these protocols. IEI currently supports three major vehicle bus protocols: OBD-II, J1939 and FMS. The OBD-II is mostly for small car diagnostics while the SAE J1939 is implemented for off-road vehicles with diesel engines and the FMS is for commercial trucks or buses. Physical Connection Interface. The vehicle bus connection is mostly based on CAN bus 2.0b signaling via a specific connection interface. For example, OBD-II defines the J1962 female 16-pin (2x8) connector as its physical interface while J1939 defines the 9-pin round connector.