AceCRC  1.1.1
Cyclic Redundancy Check (CRC) algorithms (e.g. crc16ccitt, crc32) programmatically converted from C99 code generated by pycrc (https://pycrc.org) to Arduino C++ using namespaces and PROGMEM flash memory.
crc16modbus_byte.cpp
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1 
20 #if defined(ARDUINO_ARCH_AVR) || defined(ARDUINO_ARCH_SAMD)
21  #include <avr/pgmspace.h>
22 #else
23  #include <pgmspace.h>
24 #endif
25 #include "crc16modbus_byte.hpp" // header file converted by AceCRC
26 #include <stdlib.h>
27 #include <stdint.h>
28 
29 namespace ace_crc {
30 namespace crc16modbus_byte {
31 
32 
33 
37 static const crc_t crc_table[256] PROGMEM = {
38  0x0000, 0xc0c1, 0xc181, 0x0140, 0xc301, 0x03c0, 0x0280, 0xc241,
39  0xc601, 0x06c0, 0x0780, 0xc741, 0x0500, 0xc5c1, 0xc481, 0x0440,
40  0xcc01, 0x0cc0, 0x0d80, 0xcd41, 0x0f00, 0xcfc1, 0xce81, 0x0e40,
41  0x0a00, 0xcac1, 0xcb81, 0x0b40, 0xc901, 0x09c0, 0x0880, 0xc841,
42  0xd801, 0x18c0, 0x1980, 0xd941, 0x1b00, 0xdbc1, 0xda81, 0x1a40,
43  0x1e00, 0xdec1, 0xdf81, 0x1f40, 0xdd01, 0x1dc0, 0x1c80, 0xdc41,
44  0x1400, 0xd4c1, 0xd581, 0x1540, 0xd701, 0x17c0, 0x1680, 0xd641,
45  0xd201, 0x12c0, 0x1380, 0xd341, 0x1100, 0xd1c1, 0xd081, 0x1040,
46  0xf001, 0x30c0, 0x3180, 0xf141, 0x3300, 0xf3c1, 0xf281, 0x3240,
47  0x3600, 0xf6c1, 0xf781, 0x3740, 0xf501, 0x35c0, 0x3480, 0xf441,
48  0x3c00, 0xfcc1, 0xfd81, 0x3d40, 0xff01, 0x3fc0, 0x3e80, 0xfe41,
49  0xfa01, 0x3ac0, 0x3b80, 0xfb41, 0x3900, 0xf9c1, 0xf881, 0x3840,
50  0x2800, 0xe8c1, 0xe981, 0x2940, 0xeb01, 0x2bc0, 0x2a80, 0xea41,
51  0xee01, 0x2ec0, 0x2f80, 0xef41, 0x2d00, 0xedc1, 0xec81, 0x2c40,
52  0xe401, 0x24c0, 0x2580, 0xe541, 0x2700, 0xe7c1, 0xe681, 0x2640,
53  0x2200, 0xe2c1, 0xe381, 0x2340, 0xe101, 0x21c0, 0x2080, 0xe041,
54  0xa001, 0x60c0, 0x6180, 0xa141, 0x6300, 0xa3c1, 0xa281, 0x6240,
55  0x6600, 0xa6c1, 0xa781, 0x6740, 0xa501, 0x65c0, 0x6480, 0xa441,
56  0x6c00, 0xacc1, 0xad81, 0x6d40, 0xaf01, 0x6fc0, 0x6e80, 0xae41,
57  0xaa01, 0x6ac0, 0x6b80, 0xab41, 0x6900, 0xa9c1, 0xa881, 0x6840,
58  0x7800, 0xb8c1, 0xb981, 0x7940, 0xbb01, 0x7bc0, 0x7a80, 0xba41,
59  0xbe01, 0x7ec0, 0x7f80, 0xbf41, 0x7d00, 0xbdc1, 0xbc81, 0x7c40,
60  0xb401, 0x74c0, 0x7580, 0xb541, 0x7700, 0xb7c1, 0xb681, 0x7640,
61  0x7200, 0xb2c1, 0xb381, 0x7340, 0xb101, 0x71c0, 0x7080, 0xb041,
62  0x5000, 0x90c1, 0x9181, 0x5140, 0x9301, 0x53c0, 0x5280, 0x9241,
63  0x9601, 0x56c0, 0x5780, 0x9741, 0x5500, 0x95c1, 0x9481, 0x5440,
64  0x9c01, 0x5cc0, 0x5d80, 0x9d41, 0x5f00, 0x9fc1, 0x9e81, 0x5e40,
65  0x5a00, 0x9ac1, 0x9b81, 0x5b40, 0x9901, 0x59c0, 0x5880, 0x9841,
66  0x8801, 0x48c0, 0x4980, 0x8941, 0x4b00, 0x8bc1, 0x8a81, 0x4a40,
67  0x4e00, 0x8ec1, 0x8f81, 0x4f40, 0x8d01, 0x4dc0, 0x4c80, 0x8c41,
68  0x4400, 0x84c1, 0x8581, 0x4540, 0x8701, 0x47c0, 0x4680, 0x8641,
69  0x8201, 0x42c0, 0x4380, 0x8341, 0x4100, 0x81c1, 0x8081, 0x4040
70 };
71 
72 
73 crc_t crc_reflect(crc_t data, size_t data_len)
74 {
75  unsigned int i;
76  crc_t ret;
77 
78  ret = data & 0x01;
79  for (i = 1; i < data_len; i++) {
80  data >>= 1;
81  ret = (ret << 1) | (data & 0x01);
82  }
83  return ret;
84 }
85 
86 
87 crc_t crc_update(crc_t crc, const void *data, size_t data_len)
88 {
89  const unsigned char *d = (const unsigned char *)data;
90  uint8_t tbl_idx;
91 
92  while (data_len--) {
93  tbl_idx = (crc ^ *d) & 0xff;
94  crc = ((pgm_read_word(crc_table + (tbl_idx))) ^ (crc >> 8)) & 0xffff;
95  d++;
96  }
97  return crc & 0xffff;
98 }
99 
100 } // crc16modbus_byte
101 } // ace_crc
uint16_t crc_t
The type of the CRC values.
Functions and types for CRC checks.
uint16_t crc_t
The type of the CRC values.