Preventing Bit Stuffing in CAN

Some of the drawbacks of CAN depend on bit stuffing. Stuff bits worsen both timing accuracy, because of jitters on transmission times, and data integrity, due to undesired interactions with CRC calculation. The Zero Stuff-bit (ZS) mechanism operates on conventional CAN controllers and prevents stuff bits completely all over the frame by suitably encoding the data field. ZS has been experimentally proven to decrease worst-case transmission jitters from more than 20?s to less than 0.5?s at a bit rate of 1Mb/s. It also achieves a reduction in the residual error probability of about two orders of magnitude, and ensures full coexistence with conventional CAN devices and applications. An industrial-grade ZS codec has been developed for embedded platforms, whose footprint is about 2.5KB only. Its contribution to end-to-end delays is below 12?s. This confirms that ZS can be adopted as an interim software solution to ease migration from CAN to CAN FD.