rt-thread/bsp/nuvoton/libraries/m031/StdDriver/src/nu_crc.c

100 lines
2.9 KiB
C

/**************************************************************************//**
* @file crc.c
* @version V3.00
* $Revision: 4 $
* $Date: 18/04/24 3:49p $
* @brief M031 series Cyclic Redundancy Check(CRC) driver source file
*
* @note
* SPDX-License-Identifier: Apache-2.0
* Copyright (C) 2018 Nuvoton Technology Corp. All rights reserved.
*****************************************************************************/
#include "NuMicro.h"
/** @addtogroup Standard_Driver Standard Driver
@{
*/
/** @addtogroup CRC_Driver CRC Driver
@{
*/
/** @addtogroup CRC_EXPORTED_FUNCTIONS CRC Exported Functions
@{
*/
/**
* @brief CRC Open
*
* @param[in] u32Mode CRC operation polynomial mode. Valid values are:
* - \ref CRC_CCITT
* - \ref CRC_8
* - \ref CRC_16
* - \ref CRC_32
* @param[in] u32Attribute CRC operation data attribute. Valid values are combined with:
* - \ref CRC_CHECKSUM_COM
* - \ref CRC_CHECKSUM_RVS
* - \ref CRC_WDATA_COM
* - \ref CRC_WDATA_RVS
* @param[in] u32Seed Seed value.
* @param[in] u32DataLen CPU Write Data Length. Valid values are:
* - \ref CRC_CPU_WDATA_8
* - \ref CRC_CPU_WDATA_16
* - \ref CRC_CPU_WDATA_32
*
* @return None
*
* @details This function will enable the CRC controller by specify CRC operation mode, attribute, initial seed and write data length. \n
* After that, user can start to perform CRC calculate by calling CRC_WRITE_DATA macro or CRC_DAT register directly.
*/
void CRC_Open(uint32_t u32Mode, uint32_t u32Attribute, uint32_t u32Seed, uint32_t u32DataLen)
{
CRC->SEED = u32Seed;
CRC->CTL = u32Mode | u32Attribute | u32DataLen | CRC_CTL_CRCEN_Msk;
/* Setting CRCRST bit will reload the initial seed value(CRC_SEED register) to CRC controller */
CRC->CTL |= CRC_CTL_CHKSINIT_Msk;
}
/**
* @brief Get CRC Checksum
*
* @param[in] None
*
* @return Checksum Result
*
* @details This macro gets the CRC checksum result by current CRC polynomial mode.
*/
uint32_t CRC_GetChecksum(void)
{
uint32_t ret;
switch(CRC->CTL & CRC_CTL_CRCMODE_Msk)
{
case CRC_CCITT:
case CRC_16:
ret = (CRC->CHECKSUM & 0xFFFFU);
break;
case CRC_32:
ret = (CRC->CHECKSUM);
break;
case CRC_8:
ret = (CRC->CHECKSUM & 0xFFU);
break;
default:
ret = 0U;
break;
}
return ret;
}
/*@}*/ /* end of group CRC_EXPORTED_FUNCTIONS */
/*@}*/ /* end of group CRC_Driver */
/*@}*/ /* end of group Standard_Driver */
/*** (C) COPYRIGHT 2018 Nuvoton Technology Corp. ***/