74 lines
2.3 KiB
C
Executable File
74 lines
2.3 KiB
C
Executable File
/* crc.h
|
|
Copyright 2021 Carl John Kugler III
|
|
|
|
Licensed under the Apache License, Version 2.0 (the License); you may not use
|
|
this file except in compliance with the License. You may obtain a copy of the
|
|
License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
Unless required by applicable law or agreed to in writing, software distributed
|
|
under the License is distributed on an AS IS BASIS, WITHOUT WARRANTIES OR
|
|
CONDITIONS OF ANY KIND, either express or implied. See the License for the
|
|
specific language governing permissions and limitations under the License.
|
|
*/
|
|
/* Derived from:
|
|
* SD/MMC File System Library
|
|
* Copyright (c) 2016 Neil Thiessen
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#ifndef SD_CRC_H
|
|
#define SD_CRC_H
|
|
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
/**
|
|
* @brief Calculate the CRC7 checksum for the specified data block.
|
|
*
|
|
* This function calculates the CRC7 checksum for the specified data block
|
|
* using the lookup table defined in the m_Crc7Table array.
|
|
*
|
|
* @param data The data block to be checked.
|
|
* @param length The length of the data block in bytes.
|
|
* @return The calculated checksum.
|
|
*/
|
|
__attribute__((optimize("Ofast")))
|
|
static inline char crc7(uint8_t const *data, int const length) {
|
|
extern const char m_Crc7Table[];
|
|
char crc = 0;
|
|
for (int i = 0; i < length; i++) {
|
|
crc = m_Crc7Table[(crc << 1) ^ data[i]];
|
|
}
|
|
|
|
//Return the calculated checksum
|
|
return crc;
|
|
}
|
|
|
|
/**
|
|
* @brief Calculate the CRC16 checksum for the specified data block.
|
|
*
|
|
* This function calculates the CRC16 checksum for the specified data block
|
|
* using the lookup table defined in the m_Crc7Table array.
|
|
*
|
|
* @param data The data block to be checked.
|
|
* @param length The length of the data block in bytes.
|
|
* @return The calculated checksum.
|
|
*/
|
|
uint16_t crc16(uint8_t const *data, int const length);
|
|
|
|
#endif
|
|
|
|
/* [] END OF FILE */
|