International Organization for Standardization

Road vehicles - Diagnostic communication over Controller Area Network (DoCAN) - Part 2: Transport protocol and network layer services - Third Edition
 N 15765-2

Annotation

This part of ISO 15765 specifies a transport protocol and network layer services tailored to meet the requirements of CAN based vehicle network systems on controller area networks as specified in ISO 11898-1. It has been defined in accordance with the diagnostic services established in ISO 14229-1 and ISO 15031-5 but is not limited to use with them and is also compatible with most other communication needs for in vehicle networks.

ISO 11898-1 specifies variable length CAN frames with a maximum payload size dependent on the protocol device used. A CLASSICAL CAN protocol device can transmit/receive frames with payload sizes ranging from 0 bytes to 8 bytes per frame. A CAN FD (flexible data rate) protocol device can transmit/receive frames with payload sizes from 0 bytes to 64 bytes. A CAN FD protocol device is also capable of transmitting/receiving CLASSICAL CAN frames.

The diagnostic communication over controller area network (DoCAN) protocol supports the standardized service primitive interface as specified in ISO 14229-2 (UDS).

This part of ISO 15765 provides the transport protocol and network layer services to support different application-layer implementations such as

— enhanced vehicle diagnostics (emissions-related system diagnostics beyond legislated functionality, non-emissions-related system diagnostics),

— emissions-related on-board diagnostics (OBD) as specified in ISO 15031,

— world-wide harmonized on-board diagnostics (WWH-OBD) as specified in ISO 27145, and