STM32F042F4P6 CAN出现初始化不成功

1万 · 2022-6-16 22:04

用的CubeMx配置的CAN模块，自动生存的代码。发现代码在如下位置，过不去，求助。

HAL_StatusTypeDef HAL_CAN_Init(CAN_HandleTypeDef* hcan)
{
  uint32_t status = CAN_INITSTATUS_FAILED;  /* Default init status */
  uint32_t tickstart = 0U;

  /* Check CAN handle */
  if(hcan == NULL)
  {
   return HAL_ERROR;
  }

  /* Check the parameters */
  assert_param(IS_CAN_ALL_INSTANCE(hcan->Instance));
  assert_param(IS_FUNCTIONAL_STATE(hcan->Init.TTCM));
  assert_param(IS_FUNCTIONAL_STATE(hcan->Init.ABOM));
  assert_param(IS_FUNCTIONAL_STATE(hcan->Init.AWUM));
  assert_param(IS_FUNCTIONAL_STATE(hcan->Init.NART));
  assert_param(IS_FUNCTIONAL_STATE(hcan->Init.RFLM));
  assert_param(IS_FUNCTIONAL_STATE(hcan->Init.TXFP));
  assert_param(IS_CAN_MODE(hcan->Init.Mode));
  assert_param(IS_CAN_SJW(hcan->Init.SJW));
  assert_param(IS_CAN_BS1(hcan->Init.BS1));
  assert_param(IS_CAN_BS2(hcan->Init.BS2));
  assert_param(IS_CAN_PRESCALER(hcan->Init.Prescaler));

  if(hcan->State == HAL_CAN_STATE_RESET)
  {
/* Allocate lock resource and initialize it */
hcan->Lock = HAL_UNLOCKED;
/* Init the low level hardware */
HAL_CAN_MspInit(hcan);
  }

  /* Initialize the CAN state*/
  hcan->State = HAL_CAN_STATE_BUSY;

  /* Exit from sleep mode */
  CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_SLEEP);

  /* Request initialisation */
  SET_BIT(hcan->Instance->MCR, CAN_MCR_INRQ);

  /* Get tick */
  tickstart = HAL_GetTick();

  /* Wait the acknowledge */
  while(HAL_IS_BIT_CLR(hcan->Instance->MSR, CAN_MSR_INAK))
  {代码一直在这里执行，跳不出去。感觉是硬件没应答，在其他帖子中有看到说是电源不稳，会造成这种情况，我测了电源，确认电源没问题。不知道还有其他什么情况会导致这样。。。
if((HAL_GetTick()-tickstart) > CAN_TIMEOUT_VALUE)
{
   hcan->State= HAL_CAN_STATE_TIMEOUT;
   /* Process unlocked */
   __HAL_UNLOCK(hcan);
   return HAL_TIMEOUT;
}
  }

  /* Check acknowledge */
  if (HAL_IS_BIT_SET(hcan->Instance->MSR, CAN_MSR_INAK))
  {
/* Set the time triggered communication mode */
if (hcan->Init.TTCM == ENABLE)
{
   SET_BIT(hcan->Instance->MCR, CAN_MCR_TTCM);
}
else
{
   CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_TTCM);
}

/* Set the automatic bus-off management */
if (hcan->Init.ABOM == ENABLE)
{
   SET_BIT(hcan->Instance->MCR, CAN_MCR_ABOM);
}
else
{
   CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_ABOM);
}

/* Set the automatic wake-up mode */
if (hcan->Init.AWUM == ENABLE)
{
   SET_BIT(hcan->Instance->MCR, CAN_MCR_AWUM);
}
else
{
   CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_AWUM);
}

/* Set the no automatic retransmission */
if (hcan->Init.NART == ENABLE)
{
   SET_BIT(hcan->Instance->MCR, CAN_MCR_NART);
}
else
{
   CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_NART);
}

/* Set the receive FIFO locked mode */
if (hcan->Init.RFLM == ENABLE)
{
   SET_BIT(hcan->Instance->MCR, CAN_MCR_RFLM);
}
else
{
   CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_RFLM);
}

/* Set the transmit FIFO priority */
if (hcan->Init.TXFP == ENABLE)
{
   SET_BIT(hcan->Instance->MCR, CAN_MCR_TXFP);
}
else
{
   CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_TXFP);
}

/* Set the bit timing register */
WRITE_REG(hcan->Instance->BTR, (uint32_t)(hcan->Init.Mode          |
                                          hcan->Init.SJW          |
                                          hcan->Init.BS1          |
                                          hcan->Init.BS2          |
                                          (hcan->Init.Prescaler - 1U) ));

/* Request leave initialisation */
CLEAR_BIT(hcan->Instance->MCR, CAN_MCR_INRQ);

/* Get tick */
tickstart = HAL_GetTick();

/* Wait the acknowledge */
while(HAL_IS_BIT_SET(hcan->Instance->MSR, CAN_MSR_INAK))
{
   if((HAL_GetTick()-tickstart) > CAN_TIMEOUT_VALUE)
   {
      hcan->State= HAL_CAN_STATE_TIMEOUT;

   /* Process unlocked */
   __HAL_UNLOCK(hcan);

   return HAL_TIMEOUT;
   }
}

/* Check acknowledged */
if(HAL_IS_BIT_CLR(hcan->Instance->MSR, CAN_MSR_INAK))
{
   status = CAN_INITSTATUS_SUCCESS;
}
  }

  if(status == CAN_INITSTATUS_SUCCESS)
  {
/* Set CAN error code to none */
hcan->ErrorCode = HAL_CAN_ERROR_NONE;

/* Initialize the CAN state */
hcan->State = HAL_CAN_STATE_READY;

/* Return function status */
return HAL_OK;
  }
  else
  {
/* Initialize the CAN state */
hcan->State = HAL_CAN_STATE_ERROR;

/* Return function status */
return HAL_ERROR;
  }
}

1万 · 2022-6-16 22:11

补充下：端口的配置：
void HAL_CAN_MspInit(CAN_HandleTypeDef* canHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct;
  if(canHandle->Instance==CAN)
  {
  /* USER CODE BEGIN CAN_MspInit 0 */

  /* USER CODE END CAN_MspInit 0 */
/* CAN clock enable */
__HAL_RCC_CAN1_CLK_ENABLE();

/**CAN GPIO Configuration
PA11    ------> CAN_RX
PA12    ------> CAN_TX
*/
GPIO_InitStruct.Pin = GPIO_PIN_11|GPIO_PIN_12;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF4_CAN;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* USER CODE BEGIN CAN_MspInit 1 */

  /* USER CODE END CAN_MspInit 1 */
  }
}