- Overview
- 1. Introduction
- 2. General Description of the Protocol
- 3. Document Structure
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4. Fundamentals
- 4.1. Names and Addresses
- Device Names
- Device Address
- 4.2. Parameter Group
- General
- Structure and Type of a Parameter Group
- Example of a Global Parameter Group
- Example of a Specific Parameter Group
- Parameter Groups reserved specially for the Protocol
- 4.3. Data Management
- Suspect Parameter Number (SPN)
- SLOT Definition
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5. Network Management
- Network Access
- 5.1. Address Conflict
- Solution and Configurations
- Handling in a Dynamic Network
- 6. Transport Protocols (Multi-packet Messages)
- 7. Diagnostics
Introduction
Fragmented Message
The properties of a parameter group and how they differ from a “pure” CAN message are described in chapter General Information on the Parameter Group. It is mentioned there that the data length of a PGN is not limited to 8 bytes. However, because CAN is used as a physical transport layer, a data packet with more than 8 bytes must be divided by the sender into individual packets, which can then be sent with a CAN message each. The receiver must recombine the individual fragments in their original order. A set of rules is defined for this in the J1939 standard: a so-called transport protocol.
Last modified: Thursday, 12 April 2018, 9:53 AM