SNIP_CLASSIC_CANIF_SECTION_5_6_Configuration

5.6 Configuration The CanIf design is optimized to manage CAN protocol specific capabilities and handling of the used underlying CAN Controller. The CanIf is capable to change the CAN configuration without a re-build. Therefore, the function CanIf_Init() (see [SWS_CANIF_00001]) retrieves the required CAN configuration information from configuration containers and parameters, which are specified (linked as references, or additional parameters) in Chapter 10, see Figure 10.1. This section gives a summary of the retrieved information, e.g.: • Number of CAN Controllers. The number of CAN Controllers is necessary for dispatching of transmit and receive L-PDUs and for the control of the status of the available CAN Drivers (see CanIfCtrlDrvCfg). • Number of Hardware Object Handles. To supervise transmit requests the CAN Interface needs to know the number of HTHs and the assignments between each HTH and the corresponding CAN Controller (see CanIfHthCanCtrlIdRef; CanIfHthIdSymRef). • Range of received CAN IDs passing hardware acceptance filter for each hardware object. The CAN Interface uses fixed assignments between HRHs and L-PDUs to be received in the corresponding hardware object to conduct a search algorithm (see Chapter 7.20 “Software receive filter”, see CanIfHrhSoftwareFilter, CanIfHrhCanCtrlIdRef, CanIfHrhIdSymRef) CanIf needs information about all used upper communication service layers and L-SDUs to be dispatched. The following information has to be set up at configuration time for integration of CanIf inside the AUTOSAR COM stack: • Transmitting upper layer module and transmit I-PDU for each transmit L-SDU. => Used for dispatching of transmit confirmation services (see CanIfTxPduId). • Receiving upper layer module and receive I-PDU for each receive L-SDU. => Used for L-SDU dispatching during receive indication (see CanIfRxPduId). The CanIf needs the description of the controller and the own ECU, which is connected to one or multiple CAN networks. The following information is therefore retrieved from the CAN communication matrix, part of the AUTOSAR system configuration (see CanIfTxPduCfg, CanIfRxPduCfg): • All L-PDUs received on each physical channel of this ECU. => Used for software filtering and receive L-SDU dispatch • All L-SDUs that shall be transmitted by each physical channel on this ECU. => Used for the transmit request and Transmit L-PDU dispatch • Properties of these L-PDUs (ID, Data Length). => Used for software filtering, receive indication services, Data Length Check • Transmitter for each transmitted L-SDU (i.e. PduR, CanNm, CanTp). => Used for the transmit confirmation services • Receiver for each receive L-SDU (i.e. PduR, CanNm, CanTp) => Used for the L-PDU dispatch • Symbolic L-PDU/L-SDU name. => Used for the representation of Rx/Tx data buffer addresses