/*,-----------------------------------------------------------------------------------------.| util/crc8|-----------------------------------------------------------------------------------------| this file implements some crc8 routines| - based on code by peter danegger| - ..._rev0x07 is used by mca25 mux protocol! <---- NOT REALLY TESTED! THERE MIGHT BE A HIDDEN BUG!|| Author   : {{removed according to contest rules}}|            -> circuitcellar.com avr design contest 2006|            -> Entry #AT2616||-----------------------------------------------------------------------------------------| License:| 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 2 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, write to the Free Software Foundation, Inc., 51| Franklin St, Fifth Floor, Boston, MA 02110, USA|| http://www.gnu.de/gpl-ger.html`-----------------------------------------------------------------------------------------*/#include "crc8.h"unsigned char crc8_calc(unsigned char *data, unsigned char crc_start, unsigned int len){	unsigned int i;	unsigned char crc = crc_start;	for(i=0; i<len; i++){		crc = crc8_calc_byte(crc,data[len]); //pgm_read_byte(&crc8_lookuptable[crc ^ data[len]]);	}	return crc;}//crc8, reversed, poly 0x07unsigned char crc8_calc_byte_rev0x07(unsigned char crc, unsigned char data){	data ^= crc;	crc = 0;	if( data & 0x01 ) crc  = 0x91;	if( data & 0x02 ) crc ^= 0xE3;	if( data & 0x04 ) crc ^= 0x07;	if( data & 0x08 ) crc ^= 0x0E;	if( data & 0x10 ) crc ^= 0x1C;	if( data & 0x20 ) crc ^= 0x38;	if( data & 0x40 ) crc ^= 0x70;	if( data & 0x80 ) crc ^= 0xE0;  return crc;}unsigned char crc8_calc_byte(unsigned char crc, unsigned char data){	data ^= crc;	crc = 0;	if( data & 0x01 ) crc = 0x5E;	if( data & 0x02 ) crc ^= 0xBC;	if( data & 0x04 ) crc ^= 0x61;	if( data & 0x08 ) crc ^= 0xC2;	if( data & 0x10 ) crc ^= 0x9D;	if( data & 0x20 ) crc ^= 0x23;	if( data & 0x40 ) crc ^= 0x46;	if( data & 0x80 ) crc ^= 0x8C;  return crc;}