STM32的CRC32 實現代碼 -- Ether

標籤：

uint32_t reverse_32( uint32_t data ){  asm("rbit r0,r0");  return data;};uint32_t crc32_ether( char *buf, int len, int clear ){  uint32_t *p = (uint32_t*) buf;  uint32_t crc, crc_reg;  if ( clear )    CRC_ResetDR( );  while ( len >= 4 )  {    crc_reg = CRC_CalcCRC( reverse_32( *p++ ) );    len -= 4;  }  crc = reverse_32( crc_reg );  if ( len )  {    CRC_CalcCRC( crc_reg );    switch ( len )    {      case 1:        crc_reg = CRC_CalcCRC( reverse_32( ( *p & 0xFF ) ^ crc ) >> 24 );        crc = ( crc >> 8 ) ^ reverse_32( crc_reg );        break;      case 2:        crc_reg = CRC_CalcCRC( reverse_32( ( *p & 0xFFFF ) ^ crc ) >> 16 );        crc = ( crc >> 16 ) ^ reverse_32( crc_reg );        break;      case 3:        crc_reg = CRC_CalcCRC( reverse_32( ( *p & 0xFFFFFF ) ^ crc ) >> 8 );        crc = ( crc >> 24 ) ^ reverse_32( crc_reg );        break;    }  }  return ~crc;}

 

STM32的CRC32 實現代碼 -- Ether