Wavecard-Waveport User Manual
Coronis Systems
2.2.3 Sample CRC code (C language)
This example shows how to compute CRC on a fixed frame length equal to 9.
#include
<iostream.h>
#include
<stdio.h>
#include
<string.h>
void
main ( )
{
int
Poly = 0x8408;
int
lg = 9;
unsigned int
Frame [] = { 0x0B, 0x20, 0x43, 0x06, 0x01, 0x00, 0x00, 0x02, 0X01};
unsigned int
Crc;
int
j, i_bits, carry;
Crc = 0;
for
( j=0 ; j < lg ; j++ )
{
Crc = Crc ^ Frame[j] ;
for
( i_bits=0 ; i_bits < 8 ; + )
{
carry = Crc & 1 ;
Crc = Crc / 2 ;
if
( carry )
{
Crc = Crc ^ Poly;
}
}
}
printf
( “CRC = %x “, Crc);
}
Notes:
•
The computed CRC is: 41D2 hexadecimal
•
The LSB and MSB bytes must then be inverted before storing them in the frame.
CS-SUP-MUTI-WPORTAPP-E04
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