ASAM MCD and ODX-Technology

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The ASAM (Association for Standardisation of Automation and Measuring Systems) association provides standards for data models, interfaces and syntax specifications for a great number of applications, examples, evaluations and simulations.

The ASAM-MCD standard specifies the interfaces and data exchange formats of MCD (application) systems. Those MCD systems enable the access to networked ECUs and can be installed via a GDI interface into applications, for example. So they serve for measuring, adjusting (optimising characteristic lines and values) and diagnosing. All three functional groups shall be applied as independent part systems which are combined corresponding to the application demands via standardized interfaces.

The description of interfaces and data exchange formats of the MCD systems forms the main focus of MCD. During development, production and service, all inserted MCD systems shall be compatible and exchangeable among each other to support the development process.

ASAM MCD-2D (ODX-Standard)

The comprehension of ECUs in vehicles is an important property. That comprehension shall be encapsulated of ECUs from the users view. So the user needs the access to measure and adjust objects as well as the results of diagnostic services. The ECU information must be provided in a consistent form to include and exchange ECUs.

For this reason the ASAM e.V. association defined the ASAM MCD-2D standard in May 2004 which provides all information, both demands and documentations which are relevant in vehicle and ECU diagnostics, for programming the garage tester or the software configuration in ODX format.

ODX (Open Diagnostic Data Exchange) describes the concept of using a new standardized diagnostic format for the industry to provide information out of the diagnostic data flow for the manufacturers of diagnostic tool applications. So the service support gets easier with independent repair stations. The diagnostic data modelled by ODX are compatible to the software regards of Modular Vehicle Communication Interface (MVCI).

The ODX specification contains a data model describing all diagnostic data of a vehicle or physical ECU like diagnostic error codes, data parameter, identification data, input/output parameters or communication parameters. ODX is described in UML (Unified Modelling Language); diagrams the data exchange format uses XML (Extensible Mark-up Language).

The diagnostic data modelled by ODX describe two diagnostic relevant areas of vehicle:

  • diagnostic data which are recorded in the ECU
  • diagnostic relevant data which are used from the view of the vehicle

The development, the production and the service define which communication protocol and what data shall be implemented into the ECU. That information is documented in a structured format. For that an XML standard and a corresponding ODX-XML-Editor are applied.