Safety Assurance Trailers for SAE J1939-22 C-PGs
J1939-77
This document specifies the technical requirements for several different trailers that may be incorporated into J1939-22 C-PG payloads to provide safety assurance data. Proper use of these trailers is suitable for meeting applicable functional safety standards for a given industry.
This document provides enough details for trailers that another document (likely SAE J1939-22) can incorporate these details into specific trailer formats. Accordingly, this document does not define the Type of Service (TOS) or Trailer Format (TF) values to use for these trailers, nor does it define the position of these trailers relative to other trailers that provide security assurance data.
Rationale: SAE J1939-76 defines a protocol to provide safety assurance data for SAE J1939-21 messages, which are based on Classical CAN frames with eight-byte payloads. SAE J1939-22 has defined new message formats to take advantage of the larger 64-byte payload in CAN FD frames. Accordingly, this document provides safety assurance data similar to that provided in J1939-76 but intended for trailers in C-PGs as defined in J1939-22.