Can we create a *.dbc file using *.a2l file

[pks]

Do any one know how to create a .dbc file from .a2l file. Iam using usb-8473 for my application and I have only the flash and .a2l file. I dont have any .dbc file. I want to do some kind of testing by transmitting and receiving messages. In order to get the scalled data we need the .dbc file right, so i was wondering wether we could make a .dbc from .a2l file.

Thank you,

Shanth.

[PrashantHonda]

hi did you get answer of your post, pls let me know

[Hooovahh]

You cannot convert an A2L to a DBC, they don't represent the same thing, the only thing they share is a common hardware interface.  You can't convert a flash web game to HTML even through they both work in a web browser and both use an ethernet port.

If you have an A2L file you can pull out information that is needed to send and receive raw frames to perform the same action, but there are many things that an A2L (or XCP) support that a DBC doesn't, things like multiframe messages.

[savalia93]

What to look for in A2L file if I want to make my own DBC file from it so that I can decode ECU CAN data to real values. Please can to give small example? 

[IanDeaville(ZF)]

As Hooovahh stated earlier, A2L and DBC files describe different things.  

DBC - describes all messages (frames) on the bus

A2L - describes the content of an ECU

Data from the ECU can be requested by using the data in the A2L file.  That request & any response data will be transmitted using (normally) two specific frames described in the DBC.  There will be other messages present on the bus that are described in the DBC that are nothing to do with the A2L.  

For example, consider the DBC as a catalogue of all vehicles on a highway and the A2L as a catalogue of all passengers in one specific vehicle.  It is a single highway, but just by knowing about the passengers in one vehicle we cannot extrapolate to the other vehicles on that highway.  

Regards,

Ian

[kayfh]

Hi,

A2L files are not equivalent to DBC files.

DBC files contain a mapping of CAN frame payloads to decoded data, e.g. when the ECU is sending data to other ECUs on the CAN bus during normal operation. The NI-XNET driver natively supports converting the data from/to raw CAN frames using a DBC database.

A2L files describe the memory content (measurements, calibrations) of an ECU, e.g. the name, type and location of internal variables in the ECU's RAM as well as information for flashing etc. These are usually accessed from the outside using a standardized protocol like XCP which the ECU implements. This is typically used during development of the ECU.

NI has a product called "ECU Measurement and Calibration Toolkit", it implements the XCP protocol, and therefore allows accessing the data in an XCP-compliant ECU's memory (as defined in the A2L file). Note that there may be protection mechanisms in place (e.g. private Seed&Key algorithms) that must be provided by the ECU manufacturer to gain access to the ECU.