110 lines
4.1 KiB
C
110 lines
4.1 KiB
C
/***************************************************************************
|
|
* libs/libc/misc/lib_crc8ccitt.c
|
|
*
|
|
* Licensed to the Apache Software Foundation (ASF) under one or more
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|
* this work for additional information regarding copyright ownership. The
|
|
* ASF licenses this file to you 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.
|
|
*
|
|
***************************************************************************/
|
|
|
|
/* Public domain implementation: https://3dbrew.org/wiki/CRC-8-CCITT */
|
|
|
|
/***************************************************************************
|
|
* Included Files
|
|
***************************************************************************/
|
|
|
|
#include <sys/types.h>
|
|
#include <stdint.h>
|
|
#include <crc8.h>
|
|
|
|
/***************************************************************************
|
|
* Private Data
|
|
***************************************************************************/
|
|
|
|
static const uint8_t crc8_tab[256] =
|
|
{
|
|
0x00, 0x07, 0x0e, 0x09, 0x1c, 0x1b, 0x12, 0x15,
|
|
0x38, 0x3f, 0x36, 0x31, 0x24, 0x23, 0x2a, 0x2d,
|
|
0x70, 0x77, 0x7e, 0x79, 0x6c, 0x6b, 0x62, 0x65,
|
|
0x48, 0x4f, 0x46, 0x41, 0x54, 0x53, 0x5a, 0x5d,
|
|
0xe0, 0xe7, 0xee, 0xe9, 0xfc, 0xfb, 0xf2, 0xf5,
|
|
0xd8, 0xdf, 0xd6, 0xd1, 0xc4, 0xc3, 0xca, 0xcd,
|
|
0x90, 0x97, 0x9e, 0x99, 0x8c, 0x8b, 0x82, 0x85,
|
|
0xa8, 0xaf, 0xa6, 0xa1, 0xb4, 0xb3, 0xba, 0xbd,
|
|
0xc7, 0xc0, 0xc9, 0xce, 0xdb, 0xdc, 0xd5, 0xd2,
|
|
0xff, 0xf8, 0xf1, 0xf6, 0xe3, 0xe4, 0xed, 0xea,
|
|
0xb7, 0xb0, 0xb9, 0xbe, 0xab, 0xac, 0xa5, 0xa2,
|
|
0x8f, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9d, 0x9a,
|
|
0x27, 0x20, 0x29, 0x2e, 0x3b, 0x3c, 0x35, 0x32,
|
|
0x1f, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0d, 0x0a,
|
|
0x57, 0x50, 0x59, 0x5e, 0x4b, 0x4c, 0x45, 0x42,
|
|
0x6f, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7d, 0x7a,
|
|
0x89, 0x8e, 0x87, 0x80, 0x95, 0x92, 0x9b, 0x9c,
|
|
0xb1, 0xb6, 0xbf, 0xb8, 0xad, 0xaa, 0xa3, 0xa4,
|
|
0xf9, 0xfe, 0xf7, 0xf0, 0xe5, 0xe2, 0xeb, 0xec,
|
|
0xc1, 0xc6, 0xcf, 0xc8, 0xdd, 0xda, 0xd3, 0xd4,
|
|
0x69, 0x6e, 0x67, 0x60, 0x75, 0x72, 0x7b, 0x7c,
|
|
0x51, 0x56, 0x5f, 0x58, 0x4d, 0x4a, 0x43, 0x44,
|
|
0x19, 0x1e, 0x17, 0x10, 0x05, 0x02, 0x0b, 0x0c,
|
|
0x21, 0x26, 0x2f, 0x28, 0x3d, 0x3a, 0x33, 0x34,
|
|
0x4e, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5c, 0x5b,
|
|
0x76, 0x71, 0x78, 0x7f, 0x6a, 0x6d, 0x64, 0x63,
|
|
0x3e, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2c, 0x2b,
|
|
0x06, 0x01, 0x08, 0x0f, 0x1a, 0x1d, 0x14, 0x13,
|
|
0xae, 0xa9, 0xa0, 0xa7, 0xb2, 0xb5, 0xbc, 0xbb,
|
|
0x96, 0x91, 0x98, 0x9f, 0x8a, 0x8d, 0x84, 0x83,
|
|
0xde, 0xd9, 0xd0, 0xd7, 0xc2, 0xc5, 0xcc, 0xcb,
|
|
0xe6, 0xe1, 0xe8, 0xef, 0xfa, 0xfd, 0xf4, 0xf3
|
|
};
|
|
|
|
/***************************************************************************
|
|
* Public Functions
|
|
***************************************************************************/
|
|
|
|
/***************************************************************************
|
|
* Name: crc8ccitt
|
|
*
|
|
* Description:
|
|
* Continue CRC calculation on a part of the buffer.
|
|
*
|
|
***************************************************************************/
|
|
|
|
uint8_t crc8ccittpart(FAR const uint8_t *src, size_t len, uint8_t crc8val)
|
|
{
|
|
uint8_t *pos = (uint8_t *) src;
|
|
uint8_t *end = pos + len;
|
|
|
|
while (pos < end)
|
|
{
|
|
crc8val = crc8_tab[crc8val ^ *pos];
|
|
pos++;
|
|
}
|
|
|
|
return crc8val;
|
|
}
|
|
|
|
/***************************************************************************
|
|
* Name: crc8ccitt
|
|
*
|
|
* Description:
|
|
* Return a 8-bit CRC of the contents of the 'src' buffer, length 'len
|
|
* using a CRC with the polynomial x^8+x^2+x^1+1 ("0x07" polynomial).
|
|
*
|
|
***************************************************************************/
|
|
|
|
uint8_t crc8ccitt(FAR const uint8_t *src, size_t len)
|
|
{
|
|
return crc8ccittpart(src, len, 0);
|
|
}
|