cRIO- NI 9853 Frame loss..

[RigilKumar]

Hi all

I am using cRIO- 9012 with NI 9853 Can Module in my application.

The task is to acquire the CAN Bus traffic in vehicle and store in an external USB flash drive.

But the problem is CAN modules often read non multiple of 6 elements. (i.e some time Element remaining is 22,43,45…) even FIFO is not full. This causes misalignment of frames later in my post analysis.

I tested the module with a CAN BUS Emulator setup and also with actual Vehicle data. Response is same. I temporarily fixed the problem by discarding the Frames which is non multiple by 6. But I want to know root cause and solution to fix permanently.

Thanks in Advance

Regards

Rigil Kumar

[DirkW]

Hi,

Whenever there is such a misalignment in your data it may happen because the FIFO transfer is not handled correctly or the FIFO size is not big enough and data loss occures. I ran the attached example for a while and could not see any misalignment. Could you try this example and perhaps it helps to find the problem.

My testsystem was LV 8.2.1, NI-RIO 2.3 and i logged  a bus with 50 % busload on 500 KBaud.

DirkW