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Reference Waveform

WARNING: This page is about a different car, the 2021 Hyundai Kona. However, it is still accessible from the selected car via links, so may be relevant.
G12596206Courtesy of HYUNDAI MOTOR AMERICA

CAN Communication Wave monitors signals from CAN High line and CAN Low line simultaneously. The reference value for the High Speed CAN signal is 2.5V, which is in BUS IDLE state (DIGITAL 1). If it rises to 3.5V, it is considered 'High' whereas it sets 'Low' if it drops to 1.5V.

"0" is detected when the difference between 'High' and 'Low' is greater than 2V. Also, the information can be used to determine if the 'High' and 'Low' display voltage values reverse to each other.

1 BIT can be detected by computing "SOF (Start of Frame)" that signals the beginning of a frame. It indicates an error when the "0" signal continues for over consecutive 6 BITs. Thus, check if this occurs.