写 flash

各位大侠：我读了一个TI 的软件，是写FLASH 的，我想问的是 FCTL1 = FWKEY + ERASE + EEI 使能擦除中断的意义？没看到有中断响应程序，所以不懂设中断的意义，谢谢指点！

.void write_SegD(char value)
{
  char *Flash_ptr;                          // Flash pointer
  unsigned int i;

  Flash_ptr = (char *)0x1000;               // Initialize Flash pointer
  FCTL3 = FWKEY;                            // Clear Lock bit
  FCTL1 = FWKEY + ERASE + EEI;              // Set Erase bit, allow interrupts？？？？？？？
  *Flash_ptr = 0;                           // Dummy write to erase Flash seg

  FCTL1 = FWKEY + WRT;                      // Set WRT bit for write operation

  for (i = 0; i < 64; i++)
  {
    *Flash_ptr++ = value;                   // Write value to flash
  }

  FCTL1 = FWKEY;                            // Clear WRT bit
  FCTL3 = FWKEY + LOCK;                     // Set LOCK bit
}