#include <inttypes.h>
#define CRC8INIT0x00
#define CRC8POLY0x18 //0X18 = X^8+X^5+X^4+X^0
uint8_tcrc8 ( uint8_t *data_in, uint16_t number_of_bytes_to_read )
{ uint8_t crc;
uint16_t loop_count;
uint8_t bit_counter;
uint8_t data;
uint8_t feedback_bit;
crc = CRC8INIT;
for (loop_count = 0; loop_count != number_of_bytes_to_read; loop_count++)
{ data = data_in[loop_count];
bit_counter = 8;
do
{ feedback_bit = (crc ^ data) & 0x01;
if ( feedback_bit == 0x01 )
crc = crc ^ CRC8POLY;
crc = (crc >> 1) & 0x7F;
if ( feedback_bit == 0x01 )
crc = crc | 0x80;
data = data >> 1;
bit_counter--;
}
while (bit_counter > 0);
}
return crc;
}