You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
117 lines
3.3 KiB
117 lines
3.3 KiB
3 months ago
|
/** @addtogroup crc_file CRC peripheral API
|
||
|
|
@ingroup peripheral_apis
|
||
|
|
|
||
|
|
@author @htmlonly © @endhtmlonly 2016 Cem Basoglu <cem.basoglu@web.de>
|
||
|
|
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
* This file is part of the libopencm3 project.
|
||
|
|
*
|
||
|
|
* Copyright (C) 2016 Cem Basoglu <cem.basoglu@web.de>
|
||
|
|
*
|
||
|
|
* This library is free software: you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU Lesser General Public License as published by
|
||
|
|
* the Free Software Foundation, either version 3 of the License, or
|
||
|
|
* (at your option) any later version.
|
||
|
|
*
|
||
|
|
* This library is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
* GNU Lesser General Public License for more details.
|
||
|
|
*
|
||
|
|
* You should have received a copy of the GNU Lesser General Public License
|
||
|
|
* along with this library. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
/**@{*/
|
||
|
|
|
||
|
|
#include <libopencm3/stm32/crc.h>
|
||
|
|
|
||
|
|
/*---------------------------------------------------------------------------*/
|
||
|
|
/** @brief Enable reverse output data.
|
||
|
|
|
||
|
|
Enables the reversal of the bit order of the output data.
|
||
|
|
|
||
|
|
*/
|
||
|
|
void crc_reverse_output_enable()
|
||
|
|
{
|
||
|
|
CRC_CR |= CRC_CR_REV_OUT;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*---------------------------------------------------------------------------*/
|
||
|
|
/** @brief Disable reverse output data.
|
||
|
|
|
||
|
|
Disables the reversal of the bit order of the output data.
|
||
|
|
|
||
|
|
*/
|
||
|
|
void crc_reverse_output_disable()
|
||
|
|
{
|
||
|
|
CRC_CR &= ~CRC_CR_REV_OUT;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*---------------------------------------------------------------------------*/
|
||
|
|
/** @brief Reverse input data.
|
||
|
|
|
||
|
|
Controls the reversal of the bit order of the input data
|
||
|
|
|
||
|
|
@param[in] reverse_in Unsigned int32. Reversal bit order @ref crc_rev_in.
|
||
|
|
*/
|
||
|
|
void crc_set_reverse_input(uint32_t reverse_in)
|
||
|
|
{
|
||
|
|
uint32_t reg32 = CRC_CR;
|
||
|
|
reg32 = (reg32 & ~CRC_CR_REV_IN) | reverse_in;
|
||
|
|
CRC_CR = reg32;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*---------------------------------------------------------------------------*/
|
||
|
|
/** @brief Polynomial size
|
||
|
|
|
||
|
|
Set the size of the polynomial.
|
||
|
|
|
||
|
|
@param[in] polysize Unsigned int32. Size of polynomial @ref crc_polysize.
|
||
|
|
*/
|
||
|
|
void crc_set_polysize(uint32_t polysize)
|
||
|
|
{
|
||
|
|
uint32_t reg32 = CRC_CR;
|
||
|
|
reg32 = (reg32 & ~CRC_CR_POLYSIZE) | polysize;
|
||
|
|
CRC_CR = reg32;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*---------------------------------------------------------------------------*/
|
||
|
|
/** @brief Polynomial coefficient
|
||
|
|
|
||
|
|
Set the coefficients of the polynomial to be used for CRC calculation.
|
||
|
|
If the polynomial size is less than 32-bits, the least significant bits
|
||
|
|
have to be used to program the correct value.
|
||
|
|
|
||
|
|
@note To obtain a reliable CRC calculation, any changes to the polynomial
|
||
|
|
value or size can not be performed during a CRC calculation.
|
||
|
|
As a result, if a CRC calculation is ongoing, the application must either
|
||
|
|
reset the crc unit it or perform a CRC_DR read before changing the polynomial.
|
||
|
|
|
||
|
|
@note The default polynomial value is the CRC-32 (Ethernet) polynomial: 0x4C11DB7.
|
||
|
|
|
||
|
|
@param[in] polynomial Unsigned int32. Polynomial coefficient.
|
||
|
|
*/
|
||
|
|
void crc_set_polynomial(uint32_t polynomial)
|
||
|
|
{
|
||
|
|
CRC_POL = polynomial;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*---------------------------------------------------------------------------*/
|
||
|
|
/** @brief CRC Initial value.
|
||
|
|
|
||
|
|
Sets the crc initial value.
|
||
|
|
|
||
|
|
@param[in] initial Unsigned int32. CRC initial value.
|
||
|
|
*/
|
||
|
|
void crc_set_initial(uint32_t initial)
|
||
|
|
{
|
||
|
|
CRC_INIT = initial;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**@}*/
|
||
|
|
|