- //Polynomial representations
- //
- //Normal :0x04C11DB7
- //Reversed :0xEDB88320
- //Reversed reciprocal :0x82608EDB
- unsigned long CRC_32;
- unsigned long crc32_in_c(unsigned char *p, unsigned char len)
- {
- unsigned char i,j;
- unsigned long crc = 0xffffffff;
- for(j=0;j<len;j++)
- {
- crc = crc ^ *p++;
- for (i = 0;i<8;i++)
- {
- crc = (crc >> 1) ^ (0xedb88320 & -(crc & 1));
- }
- }
- return ~crc;
- }
- //================================================
- void main()
- {
- p_data[0]=0x33;
- p_data[1]=0x34;
- p_data[2]=0x35;
- CRC_32= crc32_in_c((unsigned char *)&p_data[0], 3);
- }
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