ISO11898

The configuration structure of CanTp is described in the AUTOSAR specification. However, there is no UML description. The update priority may have been lowered since it has been followed since the OSEK era. This time, we will define the corresponding structure entity manually without using a configurator.

CanTp is based on the concept of a pair of transmitting and receiving channels. Channels can be duplicated. However, dynamic duplication is not allowed. Only static duplication is possible.

Review of AUTOSAR CanTp interfaces. I have drawn a figure of the interfaces of AUTOSAR CanTp. Each interface is defined in its own header file. But we need to be reconciled for simulation.

The AUTOSAR CanTp specification is published in AUTOSAR_SWS_CANTransportLayer. The minimum interfaces that need to be grasped are the following. CanTp_Transmit. CanTp_MainFunction. CanTp_RxIndication. CanTp_TxConfirmation. CanIf_Transmit. PduR_CanTpCopyRxData. PduR_CanTpCopyTxData. PduR_CanTpRxIndication. PduR_CanTpStartOfReception. PduR_CanTpTxConfirmation.

The body of CanTp for A-COMSTACK is cantp.c. Many header files also need to be brought in. Timer interrupt and exclusion are realized by Win32API.

A-COMSTACK, a set of communication stack BSW for AUTOSAR, is released by the TOPPERS Association. CanTp is used in this stack. A-COMSTACK can only be used commercially if you are an AUTOSAR partner. This time, it is used for learning purpose. The off-board tester side for operation check uses python can-isotp.

The code for interrupt emulation is presented. Wait for signal with WaitForSingleObject. xlCanReceive to get various information on receive, send, and error. xlEvent.tag allocates to various processes.

To realize MCAL-CANDRV, it is necessary to reproduce the receive and transmit completion interrupts. The XL driver library notifies the events of received, sent, and error via Win32API event object. Therefore, knowledge of thread and event object handling by Win32API is required.

We are now in the AUTOSAR CanTp section! AUTOSAR has a layered structure of SW-C, RTE, BSW, and MCAL. AUTOSAR CanTp is one of BSW and reproduces ISO 15765-2.