Different members of the HC11 family have EEPROM starting at different addresses; on all members, EEPROM continues from that address to the top of the processor's address space (0xffff).
This option allows gdl to compare the memory cells being programmed against this minimum. This in turn allows it to check for a common class of program errors, in which an attempt is made to place constants or code in memory addresses other than EEPROM. The input is be in hexadecimal; no leading 0x or $ is required.
NMSU Local Note: The beginning of the EEPROM on the HC11E2 is at f800.