The byte value is used to recalculate the flash memory CRC. When reaching the end of monitored memory area, the index variable is reset to 0 to start again and the calculated CRC will be compared with the stored CRC value.

In case of a CRC divergency, safety_SafeMode() will be called.

See also:: safety_SafeMode()

Returns:: void

Definition at line 199 of file safety.c.

References CRC32POLY, mg_u16MemIdx, mg_u32ApplCRC, mg_u32CalcCRC, and safety_SafeMode().

Referenced by main().

{
  UINT8   u8Help;
  UINT8   u8Idx;
  
  u8Help = pgm_read_byte(mg_u16MemIdx);
  
  /* Calculate CRC */
  for(u8Idx = 8U; u8Idx; u8Idx--)
  {
    if(((mg_u32CalcCRC & 0x80000000) ? 1U : 0U) != (u8Help & 1U))
    {
      mg_u32CalcCRC = (mg_u32CalcCRC << 1U) ^ CRC32POLY;
    }
    else
    {
      mg_u32CalcCRC <<= 1U;
    }
    u8Help >>= 1U;
  }
  
  mg_u16MemIdx++;
  
  if(mg_u16MemIdx >= MEMPOS_CRC)
  {
    mg_u32CalcCRC ^= 0xFFFFFFFFUL;
    
    /* compare CRC values */
    if(mg_u32ApplCRC != mg_u32CalcCRC)
    {
      safety_SafeMode(); /* this function never returns */
    }
    
    mg_u16MemIdx  = 0U;
    mg_u32CalcCRC = 0xFFFFFFFFUL;
  }
}

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