I have two arduino UNO from SINTRON. I have two CAN-BUS Shields v1.1 from Seeed Studio. I have two development machines.
The two CAN-BUS Shields are mounted on the two arduino cards.
The two CAN-BUS Shields have their one switch turned to the "on" position.
I have the two CAN-BUS's connected to each other with a twisted pair of wires as shown in the Seeed Wiki for CAN-BUS Shield.
I compile and load the sketch receive_check on one arduino.
I compile and load the sketch send on the other arduino.
I monitor both with their respective Serial Monitors.
They each show that the CAN.begin call fails. (i.e. mcp2515_init fails). How do you turn on DEBUG_MODE for more debug output from mcp_can.cpp?
I have tried testing these boards without connecting the CAN BUS wires. I have tried swapping the arduino boards. I have tried loading receive_check and send sketches on the opposite boards. I have tried turning the one switch to the "off" position. Nothing I have done has gotten past the CAN.begin failure.
Can some kind soul point this novice in the right direction?