STM32G474 fdcan 实用例程及代码实现

为了实现STM32G474的fdcan，您需要进行以下步骤：

1. 配置FDCAN的时钟和引脚
使用HAL库或者直接写寄存器的方式，将FDCAN的时钟和引脚进行配置。

2. 配置FDCAN的工作模式
FDCAN有两种工作模式：Classic CAN和CAN FD。您需要根据实际情况选择合适的模式。

3. 配置FDCAN的参数和过滤器
为了使FDCAN工作，您需要配置一些参数，如数据位长度、波特率等。此外，为了防止接收到无关的消息，您还需要配置过滤器。

4. 使能FDCAN
在所有配置完成后，您需要通过使能FDCAN让其开始工作。

以下是一个简单的FDCAN例程，用于发送和接收一条CAN消息：

#include "stm32g4xx_hal.h"

FDCAN_HandleTypeDef hfdcan1;

void FDCAN_Config(void)
{
  /* Configure the FDCAN peripheral */
  hfdcan1.Instance = FDCAN1;
  hfdcan1.Init.FrameFormat = FDCAN_FRAME_CLASSIC;
  hfdcan1.Init.Mode = FDCAN_MODE_NORMAL;
  hfdcan1.Init.AutoRetransmission = ENABLE;
  hfdcan1.Init.TransmitPause = DISABLE;
  hfdcan1.Init.ProtocolException = DISABLE;
  hfdcan1.Init.NominalPrescaler = 1;
  hfdcan1.Init.NominalSyncJumpWidth = 1;
  hfdcan1.Init.NominalTimeSeg1 = 6;
  hfdcan1.Init.NominalTimeSeg2 = 3;
  hfdcan1.Init.DataPrescaler = 1;
  hfdcan1.Init.DataSyncJumpWidth = 1;
  hfdcan1.Init.DataTimeSeg1 = 6;
  hfdcan1.Init.DataTimeSeg2 = 3;
  hfdcan1.Init.StdFiltersNbr = 1;
  hfdcan1.Init.ExtFiltersNbr = 0;
  hfdcan1.Init.TxFifoQueueMode = FDCAN_TX_FIFO_OPERATION;
  hfdcan1.Init.TxFifoQueueSize = 2;
  hfdcan1.Init.RxFifo0QueueSize = 2;
  hfdcan1.Init.RxFifo1QueueSize = 2;
  hfdcan1.Init.RxBuffersNbr = 0;
  hfdcan1.Init.TxEventsNbr = 0;
  if (HAL_FDCAN_Init(&hfdcan1) != HAL_OK)
  {
    Error_Handler();
  }

  /* Configure the FDCAN filter */
  FDCAN_FilterTypeDef sFilterConfig;
  sFilterConfig.IdType = FDCAN_STANDARD_ID;
  sFilterConfig.FilterIndex = 0;
  sFilterConfig.FilterType = FDCAN_FILTER_MASK;
  sFilterConfig.FilterConfig = FDCAN_FILTER_TO_RXFIFO0;
  sFilterConfig.FilterID1 = 0x321;
  sFilterConfig.FilterID2 = 0x7FF;
  if (HAL_FDCAN_ConfigFilter(&hfdcan1, &sFilterConfig) != HAL_OK)
  {
    Error_Handler();
  }

  /* Start the FDCAN module */
  if (HAL_FDCAN_Start(&hfdcan1) != HAL_OK)
  {
    Error_Handler();
  }
}

void FDCAN_Send(uint32_t id, uint8_t* data, uint32_t len)
{
  FDCAN_TxHeaderTypeDef txHeader;
  txHeader.Identifier = id;
  txHeader.IdType = FDCAN_STANDARD_ID;
  txHeader.TxFrameType = FDCAN_DATA_FRAME;
  txHeader.DataLength = len;
  txHeader.ErrorStateIndicator = FDCAN_ESI_ACTIVE;
  txHeader.BitRateSwitch = FDCAN_BRS_OFF;
  txHeader.FDFormat = FDCAN_CLASSIC_CAN;
  txHeader.TxEventFifoControl = FDCAN_NO_TX_EVENTS;
  txHeader.MessageMarker = 0;
  if (HAL_FDCAN_AddMessageToTxFifoQ(&hfdcan1, &txHeader, data) != HAL_OK)
  {
    Error_Handler();
  }
}

void FDCAN_Receive(uint32_t* id, uint8_t* data, uint32_t* len)
{
  FDCAN_RxHeaderTypeDef rxHeader;
  if (HAL_FDCAN_GetRxFifoFillLevel(&hfdcan1, FDCAN_RX_FIFO0) > 0)
  {
    if (HAL_FDCAN_GetRxMessage(&hfdcan1, FDCAN_RX_FIFO0, &rxHeader, data) != HAL_OK)
    {
      Error_Handler();
    }
    *id = rxHeader.Identifier;
    *len = rxHeader.DataLength;
  }
}

void Error_Handler(void)
{
  /* Handle errors here */
}

int main(void)
{
  /* Initialize the HAL library */
  HAL_Init();

  /* Configure the system clock */
  SystemClock_Config();

  /* Configure the FDCAN peripheral */
  FDCAN_Config();

  /* Send a message */
  uint8_t data[] = "Hello, world!";
  FDCAN_Send(0x123, data, sizeof(data));

  /* Receive a message */
  uint32_t id;
  uint8_t rxData[8];
  uint32_t len;
  FDCAN_Receive(&id, rxData, &len);

  while (1)
  {
    /* Do something */
  }
}

以上代码仅供参考，具体实现过程中请根据实际情况进行相应的修改。