To check the health of a CAN node, one can either poll for the Bus Status value, or use the CAN Error interrupt to check the Bus State. The Bus State is determined by the Tx and Rx error counters. Here the Error Poll function is shown. The return value is used to notify the user if the node is in a less than optimum state, for example Error Passive. If so, the user may wish to send warning messages, or light an LED. The handling of CAN errors is further discussed in the CAN Basics II training course, which can be viewed on Renesas Interactive (www.renesasinteractive.com).