J1939/21_202109 Data Link Layer

Revised

09/01/2021

Features
Issuing Committee
Scope
Content
The SAE J1939 documents are intended for light, medium, and heavy-duty vehicles used on or off road, as well as appropriate stationary applications which use vehicle derived components (e.g., generator sets). Vehicles of interest include, but are not limited to, on- and off-highway trucks and their trailers, construction equipment, and agricultural equipment and implements.
The purpose of these documents is to provide an open interconnect system for electronic systems. It is the intention of these documents to allow Electronic Control Units to communicate with each other by providing a standard architecture.
This particular document, SAE J1939-21, describes the data link layer using the Classical Extended Frame Format (CEFF) with 29-bit IDs, as defined in ISO 11898-1, December 2015. For SAE J1939, no alternative data link layers are permitted.
Rationale
Content
In the case when two ECUs are using Transport Protocol to transfer the same PG in both directions, and an ECU must abort one of the transfers, the existing message structure has no way to designate which transfer to abort. The addition of the direction indicator in the TP.Conn_Abort message will solve this problem and allow an ECU to select what connection to abort.
Meta TagsDetails
DOI
https://doi.org/10.4271/J1939/21_202109
Pages
54
Citation
SAE International Recommended Practice, Data Link Layer, SAE Standard J1939/21_202109, Revised September 2021, Issued July 1994, https://doi.org/10.4271/J1939/21_202109.
Additional Details
Publisher
Published
Sep 1, 2021
Product Code
J1939/21_202109
Content Type
Recommended Practice
Status
Revised
Language
English