I am happy you already want to deals with the 'heart of the matter'.
Thanks AddeD for your very pertinent comments.
I would like to add a couple of notes:
- Check the default baud rate in the specifications of your OBD?. Remember, the example default baud rate is 1Mbps. Depending on the OBD factory settings, this value could change to 500K, 250K, etc. If so, you have to change it. I.e. if you baud rate is 125K, then you have to do this:
CAN.init(CAN0, SystemCoreClock, CAN_BPS_125K);
CAN.init(CAN1, SystemCoreClock, CAN_BPS_125K);
- Try changing the transfer ID to 0x07DF. this is a standard CAN functional request. Do it as follows:
#define TEST1_CAN_TRANSFER_ID 0x07DF
Thank you and keep us posted.