1.4 CAN-TP interaction with the CAN/CAN-FD driver

CAN/CAN-FD Driver Configuration Settings

CAN-TP can select either CAN-FD or CAN as a dependent module and specifies the configurations it requires. This is selected under Peripheral Bus Type within CAN-TP's Easy View pane.  

CAN-TP configures the CAN/CAN-FD drivers with a default payload size of 8 bytes.

When using CAN-FD driver version 1.2.1 or lower, Data Bit Rate Settings (Bit Rate Switch) will need to be manually enabled to achieve full CAN-FD speed.

FIFO settings enabled and used by CAN-TP

  • FIFO Rx: selected programmatically to be FIFO 1 by CAN-TP to receive CAN/CAN-FD packets.

  • FIFO Tx: selected programmatically to be FIFO TXQ by CAN-TP to transmit CAN/CAN-FD packets. Within the CAN-FD FIFO settings the user can select a custom Payload size which will be used by the CAN-TP module. For CAN the FIFO payload size cannot be altered and is set to a default of 8-bytes. This will be defined as the CAN_TP_TRANSMISSION_DATA_LENGTH_MAX in the can_tp_config.h file.

Message IDs for RX FIFO1 settings are handled by the user

  • The user can add either an Extended ID or Standard ID in the Rx Filter to specify the device IDs CAN/CAN-FD will read in.

Generated Code

  • can_tp.h

    • Interface that defines the methods to implement.

  • can_tp.c

    • Implementation of the CAN transport protocol.

    • The adaptor is used to send frames over CAN/CAN-FD Classic.

  • can_tp_phy_adaptor.h, can_tp_phy_adaptor.c

    • Adaptor is a middle layer between CAN-TP and the CAN/CAN-FD driver files to allow for decoupling between the layers.

  • can_tp_config.h (Not shown in diagram)

    • CAN-TP files use the configurations set in this file.

Figure 3: Firmware interface diagram.