CAN/CANopen® FAQ

Q: I just implemented my node - and it does not transmit?!

A: When running your first tests, ensure that your physical network layout is correct and that you have at least one other node connected to the network operating at the same speed / baudrate.

A CAN controller cannot transmit a single message unless it is acknowledged by at least one other CAN controller. So the wiring (don't forget the termination resistors at both ends) and another node must be in place before you can test your node.

If you are using a CAN monitor or analyzer as the second node, you can confirm that your node is set to the right baudrate by transmitting a message to it from the CAN monitor or analyzer. If the monitor or analyzer is the only node in the system besides yours, try to transmit a message from it. If your controller is correctly initialized it will acknowledge the message allowing the message to be transmitted by the monitor or analyzer. Otherwise the monitor or analyzer will show a high bus load r another error.

Do you have more questions or comments on our answers?

Submit them to: info@canopen.us