/***************************************************************************//** | |
* @file | |
* @brief General Purpose Cyclic Redundancy Check (GPCRC) API. | |
* @version 5.1.2 | |
******************************************************************************* | |
* @section License | |
* <b>Copyright 2016 Silicon Laboratories, Inc. http://www.silabs.com</b> | |
******************************************************************************* | |
* | |
* Permission is granted to anyone to use this software for any purpose, | |
* including commercial applications, and to alter it and redistribute it | |
* freely, subject to the following restrictions: | |
* | |
* 1. The origin of this software must not be misrepresented; you must not | |
* claim that you wrote the original software. | |
* 2. Altered source versions must be plainly marked as such, and must not be | |
* misrepresented as being the original software. | |
* 3. This notice may not be removed or altered from any source distribution. | |
* | |
* DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Labs has no | |
* obligation to support this Software. Silicon Labs is providing the | |
* Software "AS IS", with no express or implied warranties of any kind, | |
* including, but not limited to, any implied warranties of merchantability | |
* or fitness for any particular purpose or warranties against infringement | |
* of any proprietary rights of a third party. | |
* | |
* Silicon Labs will not be liable for any consequential, incidental, or | |
* special damages, or any other relief, or for any claim by any third party, | |
* arising from your use of this Software. | |
* | |
******************************************************************************/ | |
#include "em_gpcrc.h" | |
#include "em_assert.h" | |
#if defined(GPCRC_PRESENT) && (GPCRC_COUNT > 0) | |
/***************************************************************************//** | |
* @addtogroup emlib | |
* @{ | |
******************************************************************************/ | |
/***************************************************************************//** | |
* @addtogroup GPCRC | |
* @{ | |
******************************************************************************/ | |
/******************************************************************************* | |
*************************** GLOBAL FUNCTIONS ****************************** | |
******************************************************************************/ | |
/***************************************************************************//** | |
* @brief | |
* Initialize the General Purpose Cyclic Redundancy Check (GPCRC) module. | |
* | |
* @details | |
* Use this function to configure the operational parameters of the GPCRC | |
* such as the polynomial to use and how the input should be preprocessed | |
* before entering the CRC calculation. | |
* | |
* @note | |
* This function will not copy the init value to the data register in order | |
* to prepare for a new CRC calculation. This must be done by a call | |
* to @ref GPCRC_Start before each calculation, or by using the | |
* autoInit functionality. | |
* | |
* @param[in] gpcrc | |
* Pointer to GPCRC peripheral register block. | |
* | |
* @param[in] init | |
* Pointer to initialization structure used to configure the GPCRC. | |
******************************************************************************/ | |
void GPCRC_Init(GPCRC_TypeDef * gpcrc, const GPCRC_Init_TypeDef * init) | |
{ | |
uint32_t polySelect; | |
if (init->crcPoly == 0x04C11DB7) | |
{ | |
polySelect = GPCRC_CTRL_POLYSEL_CRC32; | |
} | |
else | |
{ | |
// If not using the fixed CRC-32 polynomial then we must be using 16-bit | |
EFM_ASSERT((init->crcPoly & 0xFFFF0000) == 0); | |
polySelect = GPCRC_CTRL_POLYSEL_16; | |
} | |
gpcrc->CTRL = (((uint32_t)init->autoInit << _GPCRC_CTRL_AUTOINIT_SHIFT) | |
| ((uint32_t)init->reverseByteOrder << _GPCRC_CTRL_BYTEREVERSE_SHIFT) | |
| ((uint32_t)init->reverseBits << _GPCRC_CTRL_BITREVERSE_SHIFT) | |
| ((uint32_t)init->enableByteMode << _GPCRC_CTRL_BYTEMODE_SHIFT) | |
| polySelect | |
| ((uint32_t)init->enable << _GPCRC_CTRL_EN_SHIFT)); | |
if (polySelect == GPCRC_CTRL_POLYSEL_16) | |
{ | |
// Set CRC polynomial value | |
uint32_t revPoly = __RBIT(init->crcPoly) >> 16; | |
gpcrc->POLY = revPoly & _GPCRC_POLY_POLY_MASK; | |
} | |
// Load CRC initialization value to GPCRC_INIT | |
gpcrc->INIT = init->initValue; | |
} | |
/***************************************************************************//** | |
* @brief | |
* Reset GPCRC registers to the hardware reset state. | |
* | |
* @note | |
* The data registers are not reset by this function. | |
* | |
* @param[in] gpcrc | |
* Pointer to GPCRC peripheral register block. | |
******************************************************************************/ | |
void GPCRC_Reset(GPCRC_TypeDef * gpcrc) | |
{ | |
gpcrc->CTRL = _GPCRC_CTRL_RESETVALUE; | |
gpcrc->POLY = _GPCRC_POLY_RESETVALUE; | |
gpcrc->INIT = _GPCRC_INIT_RESETVALUE; | |
} | |
/** @} (end addtogroup GPCRC) */ | |
/** @} (end addtogroup emlib) */ | |
#endif /* defined(GPCRC_COUNT) && (GPCRC_COUNT > 0) */ |