STM32的CRC32 测试代码

// STM32 CRC32 Test App - [email protected]

#include <windows.h>
#include <stdio.h>

DWORD Crc32( DWORD Crc, DWORD Data )
{
  int i;

  Crc = Crc ^ Data;

  for ( i = 0; i < 32; i++ )
    if ( Crc & 0x80000000 )
      Crc = ( Crc << 1 ) ^ 0x04C11DB7; // Polynomial used in STM32
    else
      Crc = ( Crc << 1 );

  return ( Crc );
}

DWORD Crc32Fast( DWORD Crc, DWORD Data )
{
  static const DWORD CrcTable[ 16 ] =
  { // Nibble lookup table for 0x04C11DB7 polynomial
      0x00000000, 0x04C11DB7, 0x09823B6E, 0x0D4326D9, 0x130476DC, 0x17C56B6B,
      0x1A864DB2, 0x1E475005, 0x2608EDB8, 0x22C9F00F, 0x2F8AD6D6, 0x2B4BCB61,
      0x350C9B64, 0x31CD86D3, 0x3C8EA00A, 0x384FBDBD };

  Crc = Crc ^ Data; // Apply all 32-bits

  // Process 32-bits, 4 at a time, or 8 rounds

  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ]; // Assumes 32-bit reg, masking index to 4-bits
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ]; //  0x04C11DB7 Polynomial used in STM32
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];

  return ( Crc );
}

void test( void )
{
  BYTE vector[ 12 ] =
  {
    0x02, 0x07, 0x02, 0x00, 0x18, 0x8A, 0xD0, 0x23, 0x25, 0x2B, 0x09, 0x00 };
  DWORD Crc;
  int i;

  for ( i = 0; i < 12; i++ )
    printf( "%02X ", vector[ i ] );

  putchar( ‘\n‘ );

  Crc = 0xFFFFFFFF; // Initial state

  for ( i = 0; i < 12; i += 4 )
  {
    Crc = Crc32Fast( Crc, *( (DWORD *) &vector[ i ] ) ); // 4-bytes at a time
  }

  printf( "%08X test\n", Crc );
}

int main( int argc, char **argv )
{
  printf( "%08X\n\n", Crc32( 0xFFFFFFFF, 0x12345678 ) ); // 0xDF8A8A2B

  printf( "%08X\n\n", Crc32Fast( 0xFFFFFFFF, 0x12345678 ) ); // 0xDF8A8A2B

  test( );

  return ( 1 );
}

// STM32 CRC32 Test App - [email protected]

#include <windows.h>

#include <stdio.h>
#include <stdlib.h>

//****************************************************************************

DWORD Crc32( DWORD Crc, DWORD Data )
{
  int i;

  Crc = Crc ^ Data;

  for ( i = 0; i < 32; i++ )
    if ( Crc & 0x80000000 )
      Crc = ( Crc << 1 ) ^ 0x04C11DB7; // Polynomial used in STM32
    else
      Crc = ( Crc << 1 );

  return ( Crc );
}

//****************************************************************************

DWORD Crc32Block( DWORD Crc, DWORD Size, DWORD *Buffer ) // 32-bit units
{
  while ( Size-- )
    Crc = Crc32( Crc, *Buffer++ );

  return ( Crc );
}

//****************************************************************************

DWORD Crc32Fast( DWORD Crc, DWORD Data )
{
  static const DWORD CrcTable[ 16 ] =
  { // Nibble lookup table for 0x04C11DB7 polynomial
      0x00000000, 0x04C11DB7, 0x09823B6E, 0x0D4326D9, 0x130476DC, 0x17C56B6B,
      0x1A864DB2, 0x1E475005, 0x2608EDB8, 0x22C9F00F, 0x2F8AD6D6, 0x2B4BCB61,
      0x350C9B64, 0x31CD86D3, 0x3C8EA00A, 0x384FBDBD };

  Crc = Crc ^ Data; // Apply all 32-bits

  // Process 32-bits, 4 at a time, or 8 rounds

  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ]; // Assumes 32-bit reg, masking index to 4-bits
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ]; //  0x04C11DB7 Polynomial used in STM32
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];
  Crc = ( Crc << 4 ) ^ CrcTable[ Crc >> 28 ];

  return ( Crc );
}

//****************************************************************************

DWORD Crc32FastBlock( DWORD Crc, DWORD Size, DWORD *Buffer ) // 32-bit units
{
  while ( Size-- )
    Crc = Crc32Fast( Crc, *Buffer++ );

  return ( Crc );
}

//****************************************************************************

void test( void )
{
  BYTE vector[ 12 ] =
  {
    0x02, 0x07, 0x02, 0x00, 0x18, 0x8A, 0xD0, 0x23, 0x25, 0x2B, 0x09, 0x00 }; // ACD7E298
  DWORD Crc;
  int i;

  for ( i = 0; i < sizeof( vector ); i++ )
    printf( "%02X ", vector[ i ] );

  putchar( ‘\n‘ );

  Crc = 0xFFFFFFFF; // Initial state

  for ( i = 0; i < sizeof( vector ); i += 4 )
  {
    Crc = Crc32Fast( Crc, *( (DWORD *) &vector[ i ] ) ); // 4-bytes at a time
  }

  printf( "%08X %08X test\n", Crc,
    Crc32FastBlock( 0xFFFFFFFF, sizeof( vector ) / 4, (void *) vector ) );
}

//****************************************************************************

void TestFile( char *Filename )
{
  FILE *f;
  DWORD Size;
  BYTE *Buffer;

  f = fopen( Filename, "rb" );

  if ( f )
  {
    fseek( f, 0, SEEK_END );

    Size = ftell( f );

    fseek( f, 0, SEEK_SET );

    if ( Size & 3 )
      printf(
        "WARNING: File must be multiple of 4 bytes (32-bit) for valid results\n" );

    Buffer = malloc( Size );

    fread( Buffer, Size, 1, f );

    fclose( f );

    printf( "crc=%08X Slow\n",
      Crc32Block( 0xFFFFFFFF, Size >> 2, (void *) Buffer ) );

    printf( "crc=%08X Fast\n",
      Crc32FastBlock( 0xFFFFFFFF, Size >> 2, (void *) Buffer ) );

    free( Buffer );
  }
  else
    printf( "ERROR: Unable to open file ‘%s‘\n", Filename );
}

//****************************************************************************

int main( int argc, char **argv )
{
  printf( "STM32CRC Test\n\nUsage: STM32CRC [<file>]\n\n" );

  if ( ( Crc32( 0xFFFFFFFF, 0x12345678 ) != 0xDF8A8A2B )
    || ( Crc32Fast( 0xFFFFFFFF, 0x12345678 ) != 0xDF8A8A2B ) )
  {
    printf( "ERROR: Internal Sanity Check Failed\n" );
  }

  if ( argc > 1 )
    TestFile( argv[ 1 ] );
  else
    test( );

  return ( 1 );
}

//****************************************************************************