/**
******************************************************************************
* @file stm32h7xx_hal_crc_ex.c
* @author MCD Application Team
* @brief Extended CRC HAL module driver.
* This file provides firmware functions to manage the extended
* functionalities of the CRC peripheral.
*
******************************************************************************
* @attention
*
* Copyright (c) 2017 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
@verbatim
================================================================================
##### How to use this driver #####
================================================================================
[..]
(+) Set user-defined generating polynomial through HAL_CRCEx_Polynomial_Set()
(+) Configure Input or Output data inversion
@endverbatim
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "stm32h7xx_hal.h"
/** @addtogroup STM32H7xx_HAL_Driver
* @{
*/
/** @defgroup CRCEx CRCEx
* @brief CRC Extended HAL module driver
* @{
*/
#ifdef HAL_CRC_MODULE_ENABLED
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Exported functions --------------------------------------------------------*/
/** @defgroup CRCEx_Exported_Functions CRC Extended Exported Functions
* @{
*/
/** @defgroup CRCEx_Exported_Functions_Group1 Extended Initialization/de-initialization functions
* @brief Extended Initialization and Configuration functions.
*
@verbatim
===============================================================================
##### Extended configuration functions #####
===============================================================================
[..] This section provides functions allowing to:
(+) Configure the generating polynomial
(+) Configure the input data inversion
(+) Configure the output data inversion
@endverbatim
* @{
*/
/**
* @brief Initialize the CRC polynomial if different from default one.
* @param hcrc CRC handle
* @param Pol CRC generating polynomial (7, 8, 16 or 32-bit long).
* This parameter is written in normal representation, e.g.
* @arg for a polynomial of degree 7, X^7 + X^6 + X^5 + X^2 + 1 is written 0x65
* @arg for a polynomial of degree 16, X^16 + X^12 + X^5 + 1 is written 0x1021
* @param PolyLength CRC polynomial length.
* This parameter can be one of the following values:
* @arg @ref CRC_POLYLENGTH_7B 7-bit long CRC (generating polynomial of degree 7)
* @arg @ref CRC_POLYLENGTH_8B 8-bit long CRC (generating polynomial of degree 8)
* @arg @ref CRC_POLYLENGTH_16B 16-bit long CRC (generating polynomial of degree 16)
* @arg @ref CRC_POLYLENGTH_32B 32-bit long CRC (generating polynomial of degree 32)
* @retval HAL status
*/
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));
/* Ensure that the generating polynomial is odd */
if ((Pol & (uint32_t)(0x1U)) == 0U)
{
status = HAL_ERROR;
}
else
{
/* 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;
}
/**
* @brief Set the Reverse Input data mode.
* @param hcrc CRC handle
* @param InputReverseMode Input Data inversion mode.
* This parameter can be one of the following values:
* @arg @ref CRC_INPUTDATA_INVERSION_NONE no change in bit order (default value)
* @arg @ref CRC_INPUTDATA_INVERSION_BYTE Byte-wise bit reversal
* @arg @ref CRC_INPUTDATA_INVERSION_HALFWORD HalfWord-wise bit reversal
* @arg @ref CRC_INPUTDATA_INVERSION_WORD Word-wise bit reversal
* @retval HAL 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;
}
/**
* @brief Set the Reverse Output data mode.
* @param hcrc CRC handle
* @param OutputReverseMode Output Data inversion mode.
* This parameter can be one of the following values:
* @arg @ref CRC_OUTPUTDATA_INVERSION_DISABLE no CRC inversion (default value)
* @arg @ref CRC_OUTPUTDATA_INVERSION_ENABLE bit-level inversion (e.g. for a 8-bit CRC: 0xB5 becomes 0xAD)
* @retval HAL status
*/
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 */
/**
* @}
*/
/**
* @}
*/
