diff options
| -rw-r--r-- | nuttx/include/crc8.h | 84 | ||||
| -rw-r--r-- | nuttx/libc/misc/Make.defs | 2 | ||||
| -rw-r--r-- | nuttx/libc/misc/lib_crc8.c | 141 |
3 files changed, 226 insertions, 1 deletions
diff --git a/nuttx/include/crc8.h b/nuttx/include/crc8.h new file mode 100644 index 000000000..df8434972 --- /dev/null +++ b/nuttx/include/crc8.h @@ -0,0 +1,84 @@ +/**************************************************************************** + * include/crc8.h + * + * Copyright (C) 2014 Ken Pettit. All rights reserved. + * Author: Ken Pettit <pettitkd@gmail.com> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +#ifndef __INCLUDE_CRC8_H +#define __INCLUDE_CRC8_H + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <sys/types.h> +#include <stdint.h> + +/**************************************************************************** + * Public Function Prototypes + ****************************************************************************/ + +#ifdef __cplusplus +#define EXTERN extern "C" +extern "C" +{ +#else +#define EXTERN extern +#endif + +/**************************************************************************** + * Name: crc8part + * + * Description: + * Continue CRC calculation on a part of the buffer. + * + ****************************************************************************/ + +uint8_t crc8part(FAR const uint8_t *src, size_t len, uint8_t crc8val); + +/**************************************************************************** + * Name: crc8 + * + * Description: + * Return an 8-bit CRC of the contents of the 'src' buffer, length 'len' + * using the polynomial x^8+x^6+x^3+x^2+1 (Koopman, et al. "0xA6" poly). + * + ****************************************************************************/ + +uint8_t crc8(FAR const uint8_t *src, size_t len); + +#undef EXTERN +#ifdef __cplusplus +} +#endif + +#endif /* __INCLUDE_CRC8_H */ diff --git a/nuttx/libc/misc/Make.defs b/nuttx/libc/misc/Make.defs index 1e7a6ae05..4d0a04ac9 100644 --- a/nuttx/libc/misc/Make.defs +++ b/nuttx/libc/misc/Make.defs @@ -69,7 +69,7 @@ endif # Add the miscellaneous C files to the build -CSRCS += lib_match.c lib_crc32.c lib_crc16.c lib_dumpbuffer.c +CSRCS += lib_match.c lib_crc32.c lib_crc16.c lib_crc8.c lib_dumpbuffer.c ifeq ($(CONFIG_DEBUG),y) CSRCS += lib_dbg.c diff --git a/nuttx/libc/misc/lib_crc8.c b/nuttx/libc/misc/lib_crc8.c new file mode 100644 index 000000000..8bd10995f --- /dev/null +++ b/nuttx/libc/misc/lib_crc8.c @@ -0,0 +1,141 @@ +/************************************************************************************************ + * libc/misc/lib_crc8.c + * + * This file is a part of NuttX: + * + * Copyright (C) 2014 Ken Pettit. All rights reserved. + * Author: Ken Pettit <pettitkd@gmail.com> + * + * References: + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ************************************************************************************************/ + +/************************************************************************************************ + * Included Files + ************************************************************************************************/ + +#include <sys/types.h> +#include <stdint.h> +#include <crc8.h> + +/************************************************************************************************ + * Private Data + * + * CRC8 table generated with: + * + * #define POLY 0xB2 // ((uint8_t) 0x14D) ^ 0xFF + * + * printf(" "); + * for (y=0; y<256; y++) + * { + * crc = y; + * for (x=0; x<8; x++) + * crc = (crc & 1) ? POLY ^ (crc >> 1) : crc >> 1; + * printf("0x%02X, ", crc); + * if ((y & 0x07) == 0x7) + * printf("\n "); + * } + * + ************************************************************************************************/ + +static const uint8_t crc8_tab[256] = +{ + 0x00, 0x3e, 0x7c, 0x42, 0xf8, 0xc6, 0x84, 0xba, + 0x95, 0xab, 0xe9, 0xd7, 0x6d, 0x53, 0x11, 0x2f, + 0x4f, 0x71, 0x33, 0x0d, 0xb7, 0x89, 0xcb, 0xf5, + 0xda, 0xe4, 0xa6, 0x98, 0x22, 0x1c, 0x5e, 0x60, + 0x9e, 0xa0, 0xe2, 0xdc, 0x66, 0x58, 0x1a, 0x24, + 0x0b, 0x35, 0x77, 0x49, 0xf3, 0xcd, 0x8f, 0xb1, + 0xd1, 0xef, 0xad, 0x93, 0x29, 0x17, 0x55, 0x6b, + 0x44, 0x7a, 0x38, 0x06, 0xbc, 0x82, 0xc0, 0xfe, + 0x59, 0x67, 0x25, 0x1b, 0xa1, 0x9f, 0xdd, 0xe3, + 0xcc, 0xf2, 0xb0, 0x8e, 0x34, 0x0a, 0x48, 0x76, + 0x16, 0x28, 0x6a, 0x54, 0xee, 0xd0, 0x92, 0xac, + 0x83, 0xbd, 0xff, 0xc1, 0x7b, 0x45, 0x07, 0x39, + 0xc7, 0xf9, 0xbb, 0x85, 0x3f, 0x01, 0x43, 0x7d, + 0x52, 0x6c, 0x2e, 0x10, 0xaa, 0x94, 0xd6, 0xe8, + 0x88, 0xb6, 0xf4, 0xca, 0x70, 0x4e, 0x0c, 0x32, + 0x1d, 0x23, 0x61, 0x5f, 0xe5, 0xdb, 0x99, 0xa7, + 0xb2, 0x8c, 0xce, 0xf0, 0x4a, 0x74, 0x36, 0x08, + 0x27, 0x19, 0x5b, 0x65, 0xdf, 0xe1, 0xa3, 0x9d, + 0xfd, 0xc3, 0x81, 0xbf, 0x05, 0x3b, 0x79, 0x47, + 0x68, 0x56, 0x14, 0x2a, 0x90, 0xae, 0xec, 0xd2, + 0x2c, 0x12, 0x50, 0x6e, 0xd4, 0xea, 0xa8, 0x96, + 0xb9, 0x87, 0xc5, 0xfb, 0x41, 0x7f, 0x3d, 0x03, + 0x63, 0x5d, 0x1f, 0x21, 0x9b, 0xa5, 0xe7, 0xd9, + 0xf6, 0xc8, 0x8a, 0xb4, 0x0e, 0x30, 0x72, 0x4c, + 0xeb, 0xd5, 0x97, 0xa9, 0x13, 0x2d, 0x6f, 0x51, + 0x7e, 0x40, 0x02, 0x3c, 0x86, 0xb8, 0xfa, 0xc4, + 0xa4, 0x9a, 0xd8, 0xe6, 0x5c, 0x62, 0x20, 0x1e, + 0x31, 0x0f, 0x4d, 0x73, 0xc9, 0xf7, 0xb5, 0x8b, + 0x75, 0x4b, 0x09, 0x37, 0x8d, 0xb3, 0xf1, 0xcf, + 0xe0, 0xde, 0x9c, 0xa2, 0x18, 0x26, 0x64, 0x5a, + 0x3a, 0x04, 0x46, 0x78, 0xc2, 0xfc, 0xbe, 0x80, + 0xaf, 0x91, 0xd3, 0xed, 0x57, 0x69, 0x2b, 0x15 +}; + +/************************************************************************************************ + * Public Functions + ************************************************************************************************/ +/************************************************************************************************ + * Name: crc8part + * + * Description: + * Continue CRC calculation on a part of the buffer. + * + ************************************************************************************************/ + +uint8_t crc8part(FAR const uint8_t *src, size_t len, uint8_t crc8val) +{ + size_t i; + + crc8val ^= 0xFF; + for (i = 0; i < len; i++) + { + crc8val = crc8_tab[crc8val ^ src[i]]; + } + + return crc8val ^ 0xFF; +} + +/************************************************************************************************ + * Name: crc8 + * + * Description: + * Return a 8-bit CRC of the contents of the 'src' buffer, length 'len' using a CRC with + * the polynomial x^8+x^6+x^3+x^2+1 (Koopman, et al. "0xA6" polynomial). + * + ************************************************************************************************/ + +uint8_t crc8(FAR const uint8_t *src, size_t len) +{ + return crc8part(src, len, 0); +} + |