stm32l4xx_hal_crc_ex.c

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/* Includes ------------------------------------------------------------------*/
#include "stm32l4xx_hal.h"

#ifdef HAL_CRC_MODULE_ENABLED

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Exported functions --------------------------------------------------------*/

HAL_StatusTypeDef HAL_CRCEx_Polynomial_Set(CRC_HandleTypeDef *hcrc, uint32_t Pol, uint32_t PolyLength)
{
  HAL_StatusTypeDef status = HAL_OK;
  uint32_t msb = 31U; /* polynomial degree is 32 at most, so msb is initialized to max value */

  /* Check the parameters */
  assert_param(IS_CRC_POL_LENGTH(PolyLength));

  /* check polynomial definition vs polynomial size:
   * polynomial length must be aligned with polynomial
   * definition. HAL_ERROR is reported if Pol degree is
   * larger than that indicated by PolyLength.
   * Look for MSB position: msb will contain the degree of
   *  the second to the largest polynomial member. E.g., for
   *  X^7 + X^6 + X^5 + X^2 + 1, msb = 6. */
  while ((msb-- > 0U) && ((Pol & ((uint32_t)(0x1U) << (msb & 0x1FU))) == 0U))
  {
  }

  switch (PolyLength)
  {
    case CRC_POLYLENGTH_7B:
      if (msb >= HAL_CRC_LENGTH_7B)
      {
        status =   HAL_ERROR;
      }
      break;
    case CRC_POLYLENGTH_8B:
      if (msb >= HAL_CRC_LENGTH_8B)
      {
        status =   HAL_ERROR;
      }
      break;
    case CRC_POLYLENGTH_16B:
      if (msb >= HAL_CRC_LENGTH_16B)
      {
        status =   HAL_ERROR;
      }
      break;

    case CRC_POLYLENGTH_32B:
      /* no polynomial definition vs. polynomial length issue possible */
      break;
    default:
      status =  HAL_ERROR;
      break;
  }
  if (status == HAL_OK)
  {
    /* set generating polynomial */
    WRITE_REG(hcrc->Instance->POL, Pol);

    /* set generating polynomial size */
    MODIFY_REG(hcrc->Instance->CR, CRC_CR_POLYSIZE, PolyLength);
  }
  /* Return function status */
  return status;
}

HAL_StatusTypeDef HAL_CRCEx_Input_Data_Reverse(CRC_HandleTypeDef *hcrc, uint32_t InputReverseMode)
{
  /* Check the parameters */
  assert_param(IS_CRC_INPUTDATA_INVERSION_MODE(InputReverseMode));

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_BUSY;

  /* set input data inversion mode */
  MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_IN, InputReverseMode);
  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_READY;

  /* Return function status */
  return HAL_OK;
}

HAL_StatusTypeDef HAL_CRCEx_Output_Data_Reverse(CRC_HandleTypeDef *hcrc, uint32_t OutputReverseMode)
{
  /* Check the parameters */
  assert_param(IS_CRC_OUTPUTDATA_INVERSION_MODE(OutputReverseMode));

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_BUSY;

  /* set output data inversion mode */
  MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_OUT, OutputReverseMode);

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_READY;

  /* Return function status */
  return HAL_OK;
}




#endif /* HAL_CRC_MODULE_ENABLED */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/