Lpc2000

Hi all.

I write this code for erase flash of a LPC2106.
This code is base on some code I found on Internet.
I when to know what is a SectorStar? that resembles to?
Flash sector prepare give me a result of 7. What that mean?

Thank.

int EraseSectors(unsigned int SectorStart, unsigned int SectorEnd,
unsigned long ProcFrequency)
{
   unsigned long command[5]; 
   unsigned long result[2]; 

   IAP iap_entry = (IAP) IAP_LOCATION; 

  __disable_interrupt(); 

  command[0] = FLASH_PREPARE_SECTOR_TO_WRITE; 
  command[1] = SectorStart; 
  command[2] = SectorEnd; 
  command[3] = ProcFrequency; 

  iap_entry(command, result);

// result[0] always give me 7!!! I don't know what is this error.

  if (CMD_SUCCESS == *result) {
    command[0] = FLASH_ERASE_SECTORS; 

    iap_entry(command, result); 
  }

  __enable_interrupt(); 

   return (CMD_SUCCESS == *result);
}