CMSIS2000  0.0.7
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crc32.h
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1 /*
2  * CMSIS2000
3  * CMSIS-like sources for LPC2xxx series MCUs
4  *
5  * (C) Copyright 2011-2012, Dmitriy Cherepanov, All Rights Reserved
6  *
7  * Version: 0.0.7
8  * Date of the Last Update: 2013-03-04
9  *
10  * Permission is hereby granted, free of charge, to any person obtaining a copy
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31 #*/
32 /*----------------------------------------------------------------------------*/
33 /** Begin CRC calculation.
34  * \return CRC calc start value
35 */
36 
37 #define crc32_init() ((uint32_t)0xffffffff)
38 /*----------------------------------------------------------------------------*/
39 /** Finish CRC calculation
40  * \par crc current CRC value
41  * \return end CRC value
42  */
43 #define crc32_end(crc) (((uint32_t)(crc)) ^ ((uint32_t)0xffffffff))
44 /*----------------------------------------------------------------------------*/
45 /***\brief crc32_update
46  Calculate CRC value one at a time
47  the CRC area, and passing value to get the CRC
48  \par crc previous CRC
49  \par val8 curr data
50  \return new CRC
51 */
53 /*----------------------------------------------------------------------------*/
54 /***\brief crc32_no_comp
55  Calculate CRC for array of bytes without complement to ones.
56 
57  \par crc previous CRC (if no previous set is to 0!)
58  \par data curr data ptr
59  \par len curr data length
60 
61  \return returned value calculated CRC
62 */
63 uint32_t crc32_no_comp (uint32_t curr_crc, const uint8_t *data8, size_t len);
64 
65 /*----------------------------------------------------------------------------*/
66 /***\brief crc32
67  Calculate CRC for array of bytes
68 
69  \par crc previous CRC (if no previous set is to 0!)
70  \par data curr data ptr
71  \par len curr data length
72 
73  \return returned value calculated CRC
74 */
75 static inline uint32_t crc32 (uint32_t curr_crc, const uint8_t *data, size_t len)
76 {
77 return (crc32_end(
78  crc32_no_comp( curr_crc ^ crc32_init(),
79  data,len)
80  )
81  );
82 }
83