2 More affirmative answer (this is not a forum - see e.g. . It is a think tank (see ). edit approved Jan 12 at 21:04 Peter Mortensen 1,59933 gold badges1414 silver badges2222 bronze badges shouldn't youYou should have something more in the line of the following. if(CAN0.begin(MCP_ANY, CAN_500KBPS, MCP_16MHZ) == CAN_OK)if(CAN0.begin(MCP_ANY, CAN_500KBPS, MCP_16MHZ) == CAN_OK)  Surely you should also set up your interrupt pins and your SPI connection to the MCP2515. shouldn't you have something more in the line of if(CAN0.begin(MCP_ANY, CAN_500KBPS, MCP_16MHZ) == CAN_OK) Surely you should also set up your interrupt pins and your SPI connection to the MCP2515 You should have something more in the line of the following. if(CAN0.begin(MCP_ANY, CAN_500KBPS, MCP_16MHZ) == CAN_OK)  Surely you should also set up your interrupt pins and your SPI connection to the MCP2515. 1 answered Jan 6 at 23:56 Tjaart van aswegen 881111 bronze badges shouldn't you have something more in the line of if(CAN0.begin(MCP_ANY, CAN_500KBPS, MCP_16MHZ) == CAN_OK) Surely you should also set up your interrupt pins and your SPI connection to the MCP2515