SAE J2284/4_202211

This SAE Recommended Practice will define the physical layer and portions of the data link layer of the open systems interconnection model (ISO 7498) for a 500 kbps arbitration bus with CAN FD data at 2 Mbps high-speed CAN (HSC) protocol implementation. Both ECU and media design requirements for networks will be specified. Requirements will primarily address the CAN physical layer implementation. Requirements will focus on a minimum standard level of performance from the HSC implementation. All ECUs and media shall be designed to meet certain component level requirements in order to ensure the HSC implementation system level performance at 500 kbps arbitration bus with CAN FD data at 2 Mbps. The minimum performance level shall be specified by system level performance requirements or characteristics described in detail in Section 6 of this document. This document is designed such that if the electronic control unit (ECU) requirements defined in Section 6 are met, then the system level attributes should be obtainable. This document will address only requirements which may be tested at the ECU and media level. No requirements which apply to the testing of the HSC implementation as integrated into a vehicle are contained in this document. However, compliance with all ECU and media requirements will increase the possibility of communication compatibility between separately procured components and will greatly simplify the task of successfully integrating an HSC communication system in a vehicle. ISO 11898-1 provides a method to delay the receive sample of transmitted data to ensure proper reception of CAN FD messages when transmitting. Currently, the usage of this is defined in OEM specific documents. CAN diagnostic tool vendors generally don’t have access to the OEM documents. If this is missed, especially at 5 Mbps data rate, there may be CAN bus errors which are likely to cause the tool to go bus off. SAE J2534 references SAE J2284-4 for CAN requirements for 2 Mbps CAN FD and they would like to see it updated to include this information.