Composite ID not working

General Bugs and troubleshooting
1

Hi!

I think that the COMPOSITE_ID feature is not working as documented, or I might be making a mistake somewhere.

Here’s a sample frame from RealDash’s CAN Monitoring:

000007e8: f4 49 db 00 00 00 00 00

And here’s the XML definition:

        <frame id="0x7E8:0xF449,0,2">
            <value name="Value ABC" offset="2" length="1" conversion="V/2.55"></value>
        </frame>

Expected value would be around 85.9%, but I get zero on gauges.

I’ve seen another post from 2021 with a similar example, but no solution: https://www.realdash.net/forum/viewtopic.php?t=1348&start=10

2

Seems to be correct. One thing comes to mind is endianness, you can try to swap the bytes on composite id:

        <frame id="0x7E8:0x49F4,0,2">
            <value name="Value ABC" offset="2" length="1" conversion="V/2.55"></value>
        </frame>

Otherwise, I’m unable to troubleshoot without same CAN setup, or a CAN Monitor log and XML from you.

3

Good news, inverting the 2 bytes for the composite id worked. It was endianness after all.

I would suggest adding this as a note on the documentation to make life easier for the next ones :slight_smile: .

Thanks!

4

Done.