Distinguishing CAN from CAN FD Frames

Reserve bit to distinguish

The reserve bit of the traditional CAN frame now becomes the switch for the CAN FD format. If transferred dominant as 0, it denotes a classical CAN frame. If it contains the recessive value 1, it denotes a CAN FD frame.

FDF - Flexible Data Rate Format

The bit's new name is FDF for Flexible Data Rate Format which establishes the opportunity to transmit a much larger payload. The actual length of the data field and the decision whether to switch to a higher transmission rate or not, follow later in the frame.

Last modified: Wednesday, 22 September 2021, 4:19 PM