• Line 252: "so why are we even here?" -- because the RxCallback() will be called again after fetching an RX buffer to check for the other RX buffer. If no other RX and no error occurred, the callback loop can be terminated. It may also be that the RxCallback() loop fetches an RX that occurred after the trigger of the current loop, so the framework will call again after polling the intermediate RxCallback request, but the buffer will already be empty.
  
• Line 294: this should be a warning level log, also the "\n" at the end isn't necessary for a log.
• Code style: for readability and maintainability, please try to adopt the general coding style (at least indentation & line break / space conventions) of the module you're changing, or run a formatter on your changes before committing.
  

For receive, I'd go with what I have for now, if Michael would be so kind as to review what I have done first.  https://github.com/bitsofgreg/Open-Vehicle-Monitoring-System-3/blob/master/vehicle/OVMS.V3/components/mcp2515/mcp2515.cpp  Hopefully he'll be back on line before I get up in the morning.  Wonderful how the Earth's spin helps with the teamwork.

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Michael Balzer * Helkenberger Weg 9 * D-58256 Ennepetal
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