Programmatically import, edit and export DBC files

Credit go to @Lundin‭ for pointing me in the right direction. Kvaser has a CAN SDK free of charge. I added this to my VS22 C# project by adding "...\Kvaser\Canlib\dotnet\x64\netstandard2.0\Kvaser.KvaDbLib.dll" and "...\Kvaser\Canlib\dotnet\x64\netstandard2.0\Kvaser.CanLib.dll" to my project references.

AND (this I was stuck on)

Copying "...\Kvaser\Canlib\bin_x64\kvaDbLib.dll" to your application folder (where your executable is).

I ported a C example application from Kvaser to C# and it seems to work:

EDIT:
(Vector CANdb++) If you get unspecified syntax errors: make sure all message/signal names start with a letter and contain only letters, numbers and underscore!

(Vector CANdb++) If you get the error: "unknown symbol newly defined" make sure your are not defining two messages with e.g. the same ID.

If you want to live debug human readable J1939 messages, with offsets included, use Busmaster, it can convert the DBC file to DBF and then use the DBF to interpret the messages.

using kv = Kvaser.KvadbLib.Kvadblib;

List<string> VFrameFormat_enum_names = new() { "StandardCAN", "ExtendedCAN", "reserved", "J1939PG" };

void add_msg_to_db(kv.Hnd dbHnd, string msgName, int dlc, int msgID, out kv.MessageHnd msgHnd)
{
    kv.AddMsg(dbHnd, out msgHnd);
    kv.SetMsgName(msgHnd, msgName);
    kv.SetMsgDlc(msgHnd, dlc);
    kv.SetMsgIdEx(msgHnd, msgID);
    kv.SetMsgFlags(msgHnd, kv.MESSAGE.J1939);
}

void add_sig_to_msg
(
    kv.MessageHnd msgHnd, 
    string sigName, 
    string comment, 
    string unit, 
    kv.SignalEncoding encoding, 
    kv.SignalType type, 
    byte startBit, 
    byte length,
    double minVal,
    double maxVal,
    out kv.SignalHnd sigHnd
)
{
    kv.AddSignal(msgHnd, out sigHnd);
    kv.SetSignalName(sigHnd, sigName);
    kv.SetSignalComment(sigHnd, comment);
    kv.SetSignalUnit(sigHnd, unit);
    kv.SetSignalEncoding(sigHnd, encoding);
    kv.SetSignalRepresentationType(sigHnd, type);
    kv.SetSignalValueSize(sigHnd, startBit, length);
    kv.SetSignalValueLimits(sigHnd, minVal, maxVal);
}

kv.Open(out kv.Hnd dbHnd);
kv.Create(dbHnd, "local", null);

kv.AddAttributeDefinition(dbHnd, out kv.AttributeDefHnd ProtocolType_attr);
kv.SetAttributeDefinitionType(ProtocolType_attr, kv.AttributeType.AttributeString);
kv.SetAttributeDefinitionName(ProtocolType_attr, "ProtocolType");
kv.SetAttributeDefinitionOwner(ProtocolType_attr, kv.AttributeOwner.AttributeOwnerDb);
kv.SetAttributeDefinitionString(ProtocolType_attr, "J1939");

// This part sometimes gave me errors when opening with Vector's CANdb++ or Kvaser's database editor 3, leaving it out did not make a difference for me.
//kv.AddAttributeDefinition(dbHnd, out kv.AttributeDefHnd //VFrameFormat_attr);
//kv.SetAttributeDefinitionType(VFrameFormat_attr, //kv.AttributeType.AttributeEnumeration);
//kv.SetAttributeDefinitionName(VFrameFormat_attr, "VFrameFormat");
//kv.SetAttributeDefinitionOwner(VFrameFormat_attr, //kv.AttributeOwner.AttributeOwnerMessage);
//for (int i = 0; i < 4; i++)
    //kv.SetAttributeDefinitionString(VFrameFormat_attr, //VFrameFormat_enum_names[i], i);

add_msg_to_db(dbHnd, "TEST_MSG_000", 8, 0xC0FFEE, out kv.MessageHnd msgHand);
add_sig_to_msg(msgHand, "TEST_SIG_000", "I am a comment", "banana", kv.SignalEncoding.Intel, kv.SignalType.Unsigned, 0, 16, 0, 65535, out kv.SignalHnd sigHnd);

kv.WriteFile(dbHnd, "./testDBC.dbc");

posted 10 months ago

CC BY-SA 4.0

9mo ago

HinkyDinky‭

74 reputation 2 1 9 10