Enable RX0 Interrupts

[KMew]

Hello,

I apologize for any obvious questions, but I am new to CAN and STM32 programming.

I have written a code that successfully sends CAN messages to a CANalyzer for data interpretation, so I believe I have enabled the CAN portion correctly. My next objective is to send a message from a CANalyzer to the MCU and have it turn an LED on when it properly received the message.

I am using an evaluation board (STM32H7B3I-EVAL).

I attached a copy of my main.c file.

What I would like to know is how to enable an RX interrupt handler so that I can receive CAN data.

What do I have to add to the main.c to make that happen?

[mƎALLEm]

Hello,

In the attached main.c you’re receiving the CAN frames not in interrupt mode.

To do so you need to:

1- Enable one of the FDCAN NVIC interrupt lines (IT0 or IT1):

HAL_NVIC_SetPriority(FDCANx_IT0_IRQn, 0, 1);

HAL_NVIC_EnableIRQ(FDCANx_IT0_IRQn);

2- Activate the interrupt/notification for the RX FIFO 0:

HAL_CAN_ActivateNotification(&hfdcan1, CAN_IT_RX_FIFO0_MSG_PENDING)

3- Use the callback to read the received message:

void HAL_CAN_RxFifo0MsgPendingCallback(CAN_HandleTypeDef *hcan)
{
  /* Get RX message */
  if (HAL_CAN_GetRxMessage(hcan, CAN_RX_FIFO0, &RxHeader, RxData) != HAL_OK)
  {
    /* Reception Error */
    Error_Handler();
  }
}

You can either refer to the examples in the H7 CubeHAL package over this link: https://github.com/STMicroelectronics/STM32CubeH7/tree/master/Projects/STM32H743I-EVAL/Examples/FDCAN/FDCAN_Com_IT

Or refer to this article: 

and its related Github hotspot: 

https://github.com/stm32-hotspot/CKB-STM32-FDCAN-8Mbs

Hope that helps you as well as others ..