--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/crc8.c	Sat Jun 01 01:38:42 2013 +0800
@@ -0,0 +1,63 @@
+/* please read copyright-notice at EOF */
+
+#include <stdint.h>
+
+#define CRC8INIT    0x00
+#define CRC8POLY    0x18              //0X18 = X^8+X^5+X^4+X^0
+
+uint8_t crc8( uint8_t *data, uint16_t number_of_bytes_in_data )
+{
+	uint8_t  crc;
+	uint16_t loop_count;
+	uint8_t  bit_counter;
+	uint8_t  b;
+	uint8_t  feedback_bit;
+	
+	crc = CRC8INIT;
+
+	for (loop_count = 0; loop_count != number_of_bytes_in_data; loop_count++)
+	{
+		b = data[loop_count];
+		
+		bit_counter = 8;
+		do {
+			feedback_bit = (crc ^ b) & 0x01;
+	
+			if ( feedback_bit == 0x01 ) {
+				crc = crc ^ CRC8POLY;
+			}
+			crc = (crc >> 1) & 0x7F;
+			if ( feedback_bit == 0x01 ) {
+				crc = crc | 0x80;
+			}
+		
+			b = b >> 1;
+			bit_counter--;
+		
+		} while (bit_counter > 0);
+	}
+	
+	return crc;
+}
+
+/*
+This code is from Colin O'Flynn - Copyright (c) 2002 
+only minor changes by M.Thomas 9/2004
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/