// Copyright 2015-2020 Espressif Systems (Shanghai) PTE LTD // // 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. #pragma once #include <stdint.h> #ifdef __cplusplus extern "C" { #endif /** \defgroup crc_apis, uart configuration and communication related apis * @brief crc apis */ /** @addtogroup crc_apis * @{ */ /* Standard CRC8/16/32 algorithms. */ // CRC-8 x8+x2+x1+1 0x07 // CRC16-CCITT x16+x12+x5+1 1021 ISO HDLC, ITU X.25, V.34/V.41/V.42, PPP-FCS // CRC32: //G(x) = x32 +x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7 + x5 + x4 + x2 + x1 + 1 //If your buf is not continuous, you can use the first result to be the second parameter. /** * @brief Crc32 value that is in little endian. * * @param uint32_t crc : init crc value, use 0 at the first use. * * @param uint8_t const *buf : buffer to start calculate crc. * * @param uint32_t len : buffer length in byte. * * @return None */ uint32_t crc32_le(uint32_t crc, uint8_t const *buf, uint32_t len); /** * @brief Crc32 value that is in big endian. * * @param uint32_t crc : init crc value, use 0 at the first use. * * @param uint8_t const *buf : buffer to start calculate crc. * * @param uint32_t len : buffer length in byte. * * @return None */ uint32_t crc32_be(uint32_t crc, uint8_t const *buf, uint32_t len); /** * @brief Crc16 value that is in little endian. * * @param uint16_t crc : init crc value, use 0 at the first use. * * @param uint8_t const *buf : buffer to start calculate crc. * * @param uint32_t len : buffer length in byte. * * @return None */ uint16_t crc16_le(uint16_t crc, uint8_t const *buf, uint32_t len); /** * @brief Crc16 value that is in big endian. * * @param uint16_t crc : init crc value, use 0 at the first use. * * @param uint8_t const *buf : buffer to start calculate crc. * * @param uint32_t len : buffer length in byte. * * @return None */ uint16_t crc16_be(uint16_t crc, uint8_t const *buf, uint32_t len); /** * @brief Crc8 value that is in little endian. * * @param uint8_t crc : init crc value, use 0 at the first use. * * @param uint8_t const *buf : buffer to start calculate crc. * * @param uint32_t len : buffer length in byte. * * @return None */ uint8_t crc8_le(uint8_t crc, uint8_t const *buf, uint32_t len); /** * @brief Crc8 value that is in big endian. * * @param uint32_t crc : init crc value, use 0 at the first use. * * @param uint8_t const *buf : buffer to start calculate crc. * * @param uint32_t len : buffer length in byte. * * @return None */ uint8_t crc8_be(uint8_t crc, uint8_t const *buf, uint32_t len); /** * @} */ #ifdef __cplusplus } #endif