[proxmark3-svn] / common / crc16.c

//-----------------------------------------------------------------------------
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// CRC16
//-----------------------------------------------------------------------------

#include "crc16.h"

unsigned short update_crc16( unsigned short crc, unsigned char c )
{
  unsigned short i, v, tcrc = 0;

  v = (crc ^ c) & 0xff;
  for (i = 0; i < 8; i++) {
      tcrc = ( (tcrc ^ v) & 1 ) ? ( tcrc >> 1 ) ^ 0x8408 : tcrc >> 1;
      v >>= 1;
  }

  return ((crc >> 8) ^ tcrc)&0xffff;
}
Commit	Line	Data
bd20f8f4	1	//-----------------------------------------------------------------------------
	2	// This code is licensed to you under the terms of the GNU GPL, version 2 or,
	3	// at your option, any later version. See the LICENSE.txt file for the text of
	4	// the license.
	5	//-----------------------------------------------------------------------------
	6	// CRC16
	7	//-----------------------------------------------------------------------------
	8
fdcc61d3	9	#include "crc16.h"
	10
	11	unsigned short update_crc16( unsigned short crc, unsigned char c )
	12	{
	13	unsigned short i, v, tcrc = 0;
	14
	15	v = (crc ^ c) & 0xff;
	16	for (i = 0; i < 8; i++) {
	17	tcrc = ( (tcrc ^ v) & 1 ) ? ( tcrc >> 1 ) ^ 0x8408 : tcrc >> 1;
	18	v >>= 1;
	19	}
	20
	21	return ((crc >> 8) ^ tcrc)&0xffff;
	22	}