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CAN & CAN FD

LibXR supports both classic CAN and CAN FD. Code generation emits a driver object for every CAN/FDCAN instance and sets its transmit queue length. The peripherals and their interrupts are configured in STM32CubeMX; filters, FIFO assignment and message RAM are handled by the HAL initialization code CubeMX generates and by the LibXR drivers.

Example​

The second constructor argument is the transmit queue size used to buffer outgoing CAN frames.

static STM32CAN can1(&hcan1, 5);
static STM32CANFD fdcan1(&hfdcan1, 5);

Configuration File​

After code generation, the following configuration will appear in User/libxr_config.yaml:

CAN:
  can1:
    queue_size: 5

FDCAN:
  fdcan1:
    queue_size: 5
  • queue_size: size of the transmit queue used to buffer pending CAN/FDCAN frames.

Instances are keyed by their lower-case name. The upper-case keys of earlier versions (such as CAN1 or FDCAN1) are renamed to lower case on regeneration, keeping their settings.

Generation Rules​

  • objects are named after the lower-case instance, such as can1 or fdcan1;
  • the transmit queue length comes from CAN.<instance>.queue_size or FDCAN.<instance>.queue_size and defaults to 5;
  • with XRobot integration (--xrobot), each FDCAN object also gets a LibXR::CAN reference, see Integrate with XRobot.

After editing the file, regenerate the code with the commands in Regenerating the Code.