SNIP_CLASSIC_CANIF_FIGURE_Figure_9_1_CANINTERFACE

Figure 9.1: Transmission request with a single CAN Driver Activity Description Transmission request The upper layer initiates a transmit request via the service CanIf_Transmit(). The parameter CanTxPduId identifies the requested L-SDU. The service performs following steps: • validation of the input parameter • definition of the CAN Controller to be used The second parameter *PduInfoPtr is a pointer on the structure with transmit L-SDU related data such as SduLength and *SduDataPtr. Start transmission CanIf_Transmit() requests a transmission and calls the CanDrv service Can_Write() with corresponding processing of the HTH. Hardware request Can_Write() writes all L-PDU data in the CAN Hardware (if it is free) and sets the hardware request for transmission. E_OK from Can_Write service Can_Write() returns E_OK to CanIf_Transmit(). CAN_BUSY from Can_Write service If CanDrv detects, there are no free hardware objects available, it returns CAN_BUSY to CanIf. Copying into the buffer The L-PDU of the rejected transmit request will be inserted in the transmit buffer of CanIf until the next transmit confirmation. E_OK from CanIf CanIf_Transmit() returns E_OK to the upper layer.