1
0
mirror of https://github.com/MarlinFirmware/Marlin.git synced 2024-11-27 22:08:02 +00:00
MarlinFirmware/Marlin/src/libs/crc16.cpp
2020-07-22 22:20:14 -05:00

33 lines
1.2 KiB
C++

/**
* Marlin 3D Printer Firmware
* Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
*
* Based on Sprinter and grbl.
* Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
*/
#include "crc16.h"
void crc16(uint16_t *crc, const void * const data, uint16_t cnt) {
uint8_t *ptr = (uint8_t *)data;
while (cnt--) {
*crc = (uint16_t)(*crc ^ (uint16_t)(((uint16_t)*ptr++) << 8));
for (uint8_t i = 0; i < 8; i++)
*crc = (uint16_t)((*crc & 0x8000) ? ((uint16_t)(*crc << 1) ^ 0x1021) : (*crc << 1));
}
}