GB/T 42691.2-2023 Road vehicles - Local Interconnect Network (LIN) - Part 2: Transport protocol and network layer services
1 Scope
This document specifies a transport protocol and network layer services tailored to meet the requirements of LIN-based vehicle network systems on local interconnect networks. The protocol specifies an unconfirmed communication.
The LIN protocol supports the standardized service primitive interface as specified in ISO 14229-2.
This document provides the transport protocol and network layer services to support different application layer implementations like
——normal communication messages, and
——diagnostic communication messages.
The transport layer defines transportation of data that is contained in one or more frames. The transport layer messages are transported by diagnostic frames. A standardized API is specified for the transport layer.
Use of the transport layer is targeting systems where diagnostics are performed on the backbone bus (e.g. CAN) and where the system builder wants to use the same diagnostic capabilities on the LIN sub-bus clusters. The messages are in fact identical to the ISO 15765-2 and the PDUs carrying the messages are very similar.
The goals of the transport layer are
——low load on LIN master node,
——to provide full (or a subset thereof) diagnostics directly on the LIN slave nodes, and
——targeting clusters built with powerful LIN nodes (not the mainstream low cost).
A typical system configuration is shown in Figure 1.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 42691.3-2023 Road vehicles - Local Interconnect Network (LIN) - Part 3: Protocol specification (ISO 17987-3:2016, IDT)
ISO 14229-1 Road vehicles - Unified diagnostic services (UDS) - Part 1: Specification and requirements
Note: GB/T 40822-2021, Road vehicles - Unified diagnostic services (ISO 14229-1:2020, ISO 14229-2:2013, ISO 14229-3:2012, ISO 14229-4:2012, ISO 14229-5:2013, ISO 14229-6:2013, ISO 14229-7:2015, ISO 14229-8:2020, MOD)
ISO 14229-2 Road vehicles - Unified diagnostic services (UDS) - Part 2: Session layer services
Note: GB/T 40822-2021, Road vehicles - Unified diagnostic services (ISO 14229-1:2020, ISO 14229-2:2013, ISO 14229-3:2012, ISO 14229-4:2012, ISO 14229-5:2013, ISO 14229-6:2013, ISO 14229-7:2015, ISO 14229-8:2020, MOD)
ISO 14229-7:2015 Road vehicles - Unified diagnostic services (UDS) - Part 7: UDS on local interconnect network (UDSonLIN)
Note: GB/T 40822-2021, Road vehicles - Unified diagnostic services (ISO 14229-1:2020, ISO 14229-2:2013, ISO 14229-3:2012, ISO 14229-4:2012, ISO 14229-5:2013, ISO 14229-6:2013, ISO 14229-7:2015, ISO 14229-8:2020, MOD)
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 7498-1 and the following apply.
3.1.1
broadcast NAD
slave node receiving a message with a NAD equal to the broadcast NAD 7F16 the message is received and processed
3.1.2
configured NAD
value in the range of (0116 to 7D16 ) which is assigned to each slave node
Note 1: The assignment of configured NAD to each slave node is defined in the LDF. The configured NAD is used for node configuration and identification services, as well as UDS services according to ISO 14229-7.
Note 2: When communication is initialized configured NADs of slave nodes may be identical. The master shall assign unique configured NADs to all slave nodes before diagnostic communication begins.
Note 3: Setting or altering the configured NAD in a slave node can be done by the following ways:
——the master node assigns a new configured NAD to a slave node supporting the “Assign NAD” service;
——an API call in a slave node assigns the configured NAD;
——the configured NAD is assigned with a static configuration.
3.1.3
functional NAD
7E16 used to broadcast diagnostic requests
3.1.4
initial NAD
constant/static value in the range of (0116 to 7D16)
Note 1: initial NAD value may be derived from a pin configuration, EEPROM or slave node position detection algorithm before entering the operational state (regular LIN communication).
Note 2: The combination of initial NAD, Supplier ID and Function ID unique for each slave node is used in the “Assign NAD” command allowing an unambiguous configured NAD assignment.
Note 3: If no initial NAD is defined for a slave node (LDF, NCF) the value is identical to the configured NAD.
3.1.5
P2 timing parameter
application timing parameter for the ECU(s) and the external test equipment
3.1.6
P2 * timing parameter
enhanced response timing parameter for the ECU(s) application after response pending frame transmission
3.1.7
P4 timing parameter
timing parameter for the ECU(s) application defining the time between reception of a request and the final response
3.1.8
proprietary NAD
NAD values in the range [8016 - FF16] are used for not standardized communication purpose, such as Tier-1 slave node diagnostics
3.2 Symbols
%: percentage
µs: microsecond
ms: millisecond
|: The vertical bar indicates choice. Either the left hand side or the right hand side of the vertical bar shall appear
3.3 Abbreviated Terms
The following abbreviations apply to this document.
API: application programmers interface
BNF: Bachus-Naur format
CAN: Controller Area Network
CF: ConsecutiveFrame
FF: FirstFrame
LDF: LIN description file
L_Data: data link data
MRF: master request frame
N_AI: network address information
N_As: network layer timing parameter As
N_AsMax: timeout on As
N_Cr: network layer timing parameter Cr
N_CrMax: timeout on Cr
N_Cs: network layer timing parameter Cs
N_CsMax: timeout on Cs
N_Data: network data
N_PCI: network protocol control information
N_PCI type: network protocol control information type
N_PDU: network protocol data unit
N_SA: network source address
N_SDU: network service data unit
GB/T 42691.2-2023 Road vehicles - Local Interconnect Network (LIN) - Part 2: Transport protocol and network layer services
1 Scope
This document specifies a transport protocol and network layer services tailored to meet the requirements of LIN-based vehicle network systems on local interconnect networks. The protocol specifies an unconfirmed communication.
The LIN protocol supports the standardized service primitive interface as specified in ISO 14229-2.
This document provides the transport protocol and network layer services to support different application layer implementations like
——normal communication messages, and
——diagnostic communication messages.
The transport layer defines transportation of data that is contained in one or more frames. The transport layer messages are transported by diagnostic frames. A standardized API is specified for the transport layer.
Use of the transport layer is targeting systems where diagnostics are performed on the backbone bus (e.g. CAN) and where the system builder wants to use the same diagnostic capabilities on the LIN sub-bus clusters. The messages are in fact identical to the ISO 15765-2 and the PDUs carrying the messages are very similar.
The goals of the transport layer are
——low load on LIN master node,
——to provide full (or a subset thereof) diagnostics directly on the LIN slave nodes, and
——targeting clusters built with powerful LIN nodes (not the mainstream low cost).
A typical system configuration is shown in Figure 1.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 42691.3-2023 Road vehicles - Local Interconnect Network (LIN) - Part 3: Protocol specification (ISO 17987-3:2016, IDT)
ISO 14229-1 Road vehicles - Unified diagnostic services (UDS) - Part 1: Specification and requirements
Note: GB/T 40822-2021, Road vehicles - Unified diagnostic services (ISO 14229-1:2020, ISO 14229-2:2013, ISO 14229-3:2012, ISO 14229-4:2012, ISO 14229-5:2013, ISO 14229-6:2013, ISO 14229-7:2015, ISO 14229-8:2020, MOD)
ISO 14229-2 Road vehicles - Unified diagnostic services (UDS) - Part 2: Session layer services
Note: GB/T 40822-2021, Road vehicles - Unified diagnostic services (ISO 14229-1:2020, ISO 14229-2:2013, ISO 14229-3:2012, ISO 14229-4:2012, ISO 14229-5:2013, ISO 14229-6:2013, ISO 14229-7:2015, ISO 14229-8:2020, MOD)
ISO 14229-7:2015 Road vehicles - Unified diagnostic services (UDS) - Part 7: UDS on local interconnect network (UDSonLIN)
Note: GB/T 40822-2021, Road vehicles - Unified diagnostic services (ISO 14229-1:2020, ISO 14229-2:2013, ISO 14229-3:2012, ISO 14229-4:2012, ISO 14229-5:2013, ISO 14229-6:2013, ISO 14229-7:2015, ISO 14229-8:2020, MOD)
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 7498-1 and the following apply.
3.1.1
broadcast NAD
slave node receiving a message with a NAD equal to the broadcast NAD 7F16 the message is received and processed
3.1.2
configured NAD
value in the range of (0116 to 7D16 ) which is assigned to each slave node
Note 1: The assignment of configured NAD to each slave node is defined in the LDF. The configured NAD is used for node configuration and identification services, as well as UDS services according to ISO 14229-7.
Note 2: When communication is initialized configured NADs of slave nodes may be identical. The master shall assign unique configured NADs to all slave nodes before diagnostic communication begins.
Note 3: Setting or altering the configured NAD in a slave node can be done by the following ways:
——the master node assigns a new configured NAD to a slave node supporting the “Assign NAD” service;
——an API call in a slave node assigns the configured NAD;
——the configured NAD is assigned with a static configuration.
3.1.3
functional NAD
7E16 used to broadcast diagnostic requests
3.1.4
initial NAD
constant/static value in the range of (0116 to 7D16)
Note 1: initial NAD value may be derived from a pin configuration, EEPROM or slave node position detection algorithm before entering the operational state (regular LIN communication).
Note 2: The combination of initial NAD, Supplier ID and Function ID unique for each slave node is used in the “Assign NAD” command allowing an unambiguous configured NAD assignment.
Note 3: If no initial NAD is defined for a slave node (LDF, NCF) the value is identical to the configured NAD.
3.1.5
P2 timing parameter
application timing parameter for the ECU(s) and the external test equipment
3.1.6
P2 * timing parameter
enhanced response timing parameter for the ECU(s) application after response pending frame transmission
3.1.7
P4 timing parameter
timing parameter for the ECU(s) application defining the time between reception of a request and the final response
3.1.8
proprietary NAD
NAD values in the range [8016 - FF16] are used for not standardized communication purpose, such as Tier-1 slave node diagnostics
3.2 Symbols
%: percentage
µs: microsecond
ms: millisecond
|: The vertical bar indicates choice. Either the left hand side or the right hand side of the vertical bar shall appear
3.3 Abbreviated Terms
The following abbreviations apply to this document.
API: application programmers interface
BNF: Bachus-Naur format
CAN: Controller Area Network
CF: ConsecutiveFrame
FF: FirstFrame
LDF: LIN description file
L_Data: data link data
MRF: master request frame
N_AI: network address information
N_As: network layer timing parameter As
N_AsMax: timeout on As
N_Cr: network layer timing parameter Cr
N_CrMax: timeout on Cr
N_Cs: network layer timing parameter Cs
N_CsMax: timeout on Cs
N_Data: network data
N_PCI: network protocol control information
N_PCI type: network protocol control information type
N_PDU: network protocol data unit
N_SA: network source address
N_SDU: network service data unit
