Nordic stack and drivers for the mbed BLE API
Fork of nRF51822 by
TARGET_MCU_NRF51822/sdk/source/libraries/crc16/crc16.c
- Committer:
- Vincent Coubard
- Date:
- 2016-09-14
- Revision:
- 638:c90ae1400bf2
File content as of revision 638:c90ae1400bf2:
/* * Copyright (c) Nordic Semiconductor ASA * All rights reserved. * * 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 of Nordic Semiconductor ASA nor the names of other * contributors to this software 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 HOLDER 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. * */ #include "crc16.h" #include <stdio.h> uint16_t crc16_compute(const uint8_t * p_data, uint32_t size, const uint16_t * p_crc) { uint32_t i; uint16_t crc = (p_crc == NULL) ? 0xffff : *p_crc; for (i = 0; i < size; i++) { crc = (unsigned char)(crc >> 8) | (crc << 8); crc ^= p_data[i]; crc ^= (unsigned char)(crc & 0xff) >> 4; crc ^= (crc << 8) << 4; crc ^= ((crc & 0xff) << 4) << 1; } return crc; }