Diagnostic communication workflow in Classic AUTOSAR
Figure 4.8 shows the typical flow for diagnostic communication. Diagnostic requests flow from the Ethernet driver to Diagnostic Communication Manager (DCM). DCM will process the request and delegate it to the application if any additional processing is required. In the case of DoIP, initial communication occurs over UDP and will later switch to TCP.
Figure 4.8 – Classic AUTOSAR with DoIP
The AUTOSAR components shown in Figure 4.8 can be categorized into the following elements that are essential for remote diagnostics:
- Network setup: EthTrcv, Eth, and EthSwt establish the physical and data link layer infrastructure, with EthIf providing a uniform interface for upper layers.
- Communication management: EthSM oversees the operational state of the Ethernet communication, ensuring readiness for data transmission.
- IP networking: TCP/IP enables the establishment of IP-based communication, crucial for diagnostics over Ethernet.
- Service location and connection management: Sd discovers diagnostic services, while SoAd manages the socket connections needed for protocol-specific communication, including DoIP for diagnostics.
- Diagnostics processing: DoIP facilitates the transmission of diagnostic messages over IP. DCM manages the diagnostic logic, handling requests and responses between external diagnostic tools and vehicle ECUs.
- System coordination: NVM stores diagnostic session data persistently, ComM optimizes communication channels, BswM orchestrates software module interactions, and NM ensures network integrity and management.
- Software integration: RTE acts as a conduit, enabling seamless communication between the application layer (diagnostic services) and lower-level software modules, ensuring that diagnostics can be performed remotely with high efficiency and reliability.
In the next section, let’s gain an insight into diagnostic service management, a key enabler of diagnostic functionality in Adaptive AUTOSAR.
