SNIP_CLASSIC_CANIF_SECTION_7_10_Transmit_data_flow

7.10 Transmit data flow The Transmit Request service CanIf_Transmit() is based on L-PDUs. The access to the L-SDU specific data is organized by the following parameters: • Transmit L-PDU => L-SDU ID • Reference to a data structure, which contains L-SDU related data: Pointer to the L-SDU, pointer to the MetaData and L-SDU length. The reference to the L-SDU data structure is used as a parameter in several CanIf’s API services, e.g. CanIf_Transmit() or the callback service LSduR_CanIfRxIndication(). In case the L-PDU is configured for triggered transmission, the L-SDU pointer is a null pointer. Upper layers call CanIf_Transmit() Call of Can_Write() CAN Hardware is free? CanIf_Transmit() returns with E_OK «datastore» Copy data into CAN hardware Set transmit request in CAN controller «datastore» Copy data into transmit buffer
      
   
     

               «datastore» Queue transmit request Trigger-transmit PDU? [Yes] [No] [No] [Yes] Figure 7.5: Transmit data flow CanIf stores information about the available hardware objects configured for transmission purposes. The function CanIf_Transmit() maps the CanTxPduId to the corresponding HTH and calls the function Can_Write() or CanXL_Write(). [SWS_CANIF_00904] Upstream requirements: SRS_Can_01172 ⌈If Bus Mirroring is enabled globally (see CanIfBusMirroringSupport) and has been activated with a call to CanIf_EnableBusMirroring() for a CAN Controller, the CanIf shall store the content of each frame before it is transmitted on that controller with Can_Write().⌋ Note: The frame content should only be provided to the Bus Mirroring module when it was actually sent. Therefore, the content has to be stored so that it can be provided to the Bus Mirroring module from within the CanIf_TxConfirmation().