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Massive CAN.Error.BusOff Events and no Acknowledgments from FEZ Cobra



I’m new to the .Net Micro Framework world and EMX&FEZ Cobra.

One of my first challenges is to communicate with a car simulator over CAN.
I copied the example from the documentation which ships with the 1.0.13 SDK and I’m getting CAN messages (-> that was fast).

But I have two problems:
After getting 3~5 DataReceivedEvents I get a ErrorReceivedEvent with CAN.Error.BusOff which resets the CAN Bus, after that 3~5 DataReceivedEvents -> ErrorReceivedEvent -> and so on…
It seems the messages aren’t acknowledged, the simulator gets a buffer overflow (if i connect another device, which we use infield, the buffer overflow disappears).

Please help.
Thank you.



Check your bit timing. CAN bus bit timing can be very very tricky.